REGULATION OF ENZYME ACTIVITY. Medical Biochemistry, Lecture 25
|
|
- Helen Williamson
- 6 years ago
- Views:
Transcription
1 REGULATION OF ENZYME ACTIVITY Medical Biochemistry, Lecture 25
2 Lecture 25, Outline General properties of enzyme regulation Regulation of enzyme concentrations Allosteric enzymes and feedback inhibition Other effectors of catalytic activity
3 Metabolic Homeostasis
4 General Properties: Regulatory Enzymes The biochemical pathways that you will soon be studying are composed of groups of coordinated enzymes that perform a specific metabolic process. In general, these enzyme groups are composed of many enzymes, only a few of which are regulated by the mechanisms described in this lecture. Regulatory enzymes are usually the enzymes that are the ratelimiting, or committed step, in a pathway, meaning that after this step a particular reaction
5 Frequently, regulatory enzymes are at or near the initial steps in a pathway, or part of a branch point or cross-over point between pathways (where a metabolite can be potentially converted into several products in different pathways). In general, a cell needs to conserve energy - therefore costly (in metabolic terms) biosynthetic reaction pathways will not be operational unless a particular metabolite is required at a given General Properties: Regulatory Enzymes (cont)
6 Recall that when acting as catalysts, enzyme mediated-reactions should be reversible. However, regulatory enzymes frequently catalyze thermodynamically irreversible reactions, that is, a large negative free energy change (- G) greatly favors formation of a given metabolic product rather than the reverse reaction. Thus, regulation of enzyme activity, usually at the committed step of the pathway, is critical for supplying and maintaining cellular metabolitic and energy homeostasis. General Properties: Regulatory Enzymes (cont)
7 Two General Mechanisms that Affect Enzyme Activity: 1) control of the overall quantities of enzyme or concentration of substrates present 2) alteration of the catalytic efficiency of the enzyme
8
9 Regulation of Enzyme Concentrations The overall synthesis and degradation of a particular enzyme, also termed its turnover number, is one way of regulating the quantity of an enzyme. The amount of an enzyme in a cell can be increased by increasing its rate of synthesis, decreasing the rate of its degradation, or both.
10 Induction (an increase caused by an effector molecule) of enzyme synthesis is a common mechanism - this can manifest itself at the level of gene expression, RNA translation, and posttranslational modifications. The actions of many hormones and/or growth factors on cells will ultimately lead to an increase in the expression and translation of "new" enzymes not present prior to the signal. These generalizations will be covered in more detail in Dr. Bannon's lectures. Regulation of Enzyme Concentrations: Induction
11 The degradation of proteins is constantly occuring in the cell, yet the molecular mechanisms that determine when and which enzymes will be degraded are poorly understood. The turnover number of an enzyme can be used for general comparison with other enzymes or other enzyme systems, yet these numbers can vary from minutes to hours to days for different enzymes. Regulation of Enzyme Concentrations: Degradation
12 Protein degradation by proteases is compartmentalized in the cell in the lysosome (which is generally non-specific), or in macromolecular complexes termed proteasomes. Degradation by proteasomes is regulated by a complex pathway involving transfer of a 76 aa polypeptide, ubiquitin, to targeted proteins. Ubiquination of protein targets it for degradation by the proteasome. This pathway is highly conserved in eukaryotes, but still poorly understood Regulation of Enzyme Concentrations: Degradation (cont)
13 Regulation of Enzyme Concentrations: Degradation (cont) Proteolytic degradation is an irreversible mechanism. For examples, rapid proteolytic degradation of enzymes that were activated in response to some stimulus (for example, in a signal transduction response). This type of down-regulation allows for a transient response to a stimulus instead of a continual response. Establishing the links between proteasomes, ubiquination and signal transduction pathways is currently a very active research area
14 Zymogens: Inactive Precursor Proteins A clinically important mechanism of controlling enzyme activity is the case of protease enzymes involved (predominantly) in food digestion and blood clotting. Protease enzymes (enzymes that degrade proteins) like pepsin, trypsin and chymotrypsin are synthesized first as larger, inactive precursor proteins termed zymogens (specifically pepsinogen, trypsinogen, and chymotrypsinogen, respectively).
15 Zymogen Protease Examples Chymotrypsinogen cleavage sites to yield active chymotrypsin
16 Zymogens (cont) Activation of zymogens by proteolytic cleavage result in irreversible activation. Zymogen forms allow proteins to be transported or stored in inactive forms that can be readily converted to active forms in response to some type of cellular signal. Thus they represent a mechanism whereby the levels of an enzyme/protein can be rapidly increased (post-translationally). Other examples of zymogens include proinsulin, procollagen and many blood clotting
17 Enzyme/Substrate Compartmentation Segregation of metabolic processes into distinct subcellular locations like the cytosol or specialized organelles (nucleus, endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria, etc.) is another form of regulation. Enzymes associated with a given pathway frequently form organized, multi-component macromolecular complexes that perform a particular cellular process. Similarly, it follows that the substrates associated with a given pathway can also be localized to the same organelle or cytosolic location. This segregation
18 Enzyme Regulation by Compartmentation
19 Allosteric Enzymes Allosteric enzymes - from the Greek allos for "other" and stereos for "shape" (or site) meaning "other site". These enzymes function through reversible, non-covalent binding of a regulatory metabolite at a site other than the catalytic, active site. When bound, these metabolites do not participate in catalysis directly, but lead to conformational changes in one part of an enzyme that then affect the overall conformation of the active site (causing an increase or decrease in activity, hence these metabolites are termed allosteric activators or
20 Allosteric Example Feedback Inhibition - This occurs when an end-product of a pathway accumulates as the metabolic demand for it declines. This end-product in turn binds to the regulatory enzyme at the start of the pathway and decreases its activity - the greater the end-product levels the greater the inhibition of enzyme activity. This can either effect the K m or V max of the enzyme reaction.
21 Metabolic Pathway Product/ Feedback Inhibition
22 Allosteric Enzymes - Properties Allosteric enzymes differ from other enzymes in that they are generally larger in mass and are composed of multiple subunits containing active sites and regulatory molecule binding sites. The same principles that govern binding of a substrate to an active site are similar for an allosteric regulator molecule binding to its regulatory site.
23 Kinetics of Allosteric Enzymes - Terms Cooperativity - in relation to multiple subunit enzymes, changes in the conformation of one subunit leads to conformational changes in adjacent subunits. These changes occur at the tertiary and quaternary levels of protein organization and can be caused by an allosteric regulator. Homotropic regulation - when binding of one molecule to a multi-subunit enzyme causes a conformational shift that affects the binding of the same molecule to another subunit of the enzyme. Heterotropic regulation - when binding of one molecule to a multi-subunit enzyme affects the binding of a different molecule to this enzyme (Note: These
24 Allosteric Enzymes - Kinetics Allosteric enzymes do exhibit saturation kinetics at high [S], but they have a characteristic sigmoidal saturation curve rather than hyperbolic curve when v o is plotted versus [S] (analogous to the oxygen saturation curves of myoglobin vs. hemoglobin). Addition of an allosteric activator (+) tends to shift the curve to a more hyperbolic profile (more like Michaelis-Menten curves), while an allosteric inhibitor (-) will result in more pronounced sigmoidal curves. The sigmoidicity is thought to result from the cooperativity of structural changes between enzyme subunits (again similar to oxygen binding to hemoglobin). NOTE: A true Km cannot be determined
25 V o vs [S] for Allosteric Enzymes
26 Models of Allosteric Proteins
27 Regulation by Modulator Proteins - Calmodulin Calmodulin is a small protein (17 kda) that can bind up to four calcium ions (blue dots) in the two globular domains. When calciumis bound, calmodulin acts as a protein co-factor to stimulate the activity of target regulatory kinases like phosphorylase kinase, myosin kinase, Ca-ATPase and a Ca/calmodulin-dependent protein kinase. It is the structural conformation of Ca-calmodulin that makes it an active co-factor
28 Regulation of Enzyme Activity by Covalent Modifications Another common regulatory mechanism is the reversible covalent modification of an enzyme. Phosphorylation, whereby a phosphate is transferred from an activated donor (usually ATP) to an amino acid on the regulatory enyme, is the most common example of this type of regulation. Frequently this phosphorylation occurs in response to some stimulus (like a hormone or growth factor) that will either activate or inactivate target enzymes via
29 Phosphorylation/Signal Transduction Phosphorylation of one enzyme can lead to phosphorylation of a different enzyme which in turn acts on another enzyme, and so on. An example of this type of phosphorylation cascade is the response of a cell to cyclic AMP and its effect on glycogen metabolism. Use of a phosphorylation cascade allows a cell to respond to a signal at the cell surface and transmit the effects of that signal to intracellular enzymes (usually within the cytosol and nucleus) that modify a cellular process. This process is generically referred to as being part
30 Signaling Regulation of Glycogen Synthase and Phosphorylase A-forms, most active B-forms, less active
31 Other covalent modificiations: Prenylation, Myristoylation, Palmitoylation: The covalent addition of hydrophobic, acyl fatty acid or isoprenoid groups to soluble proteins/enzymes can alter their intracellular location. This type of hydrophobic acylation generally causes target proteins to associate with a membrane rather than the cytosol. Thus, it represents a mechanistic and functional re-compartmentalization of the target protein/enzyme (an example of a prenylated protein is the Ras oncogene discussed in lecture 11)
32 Allosteric and Phosphorylation Regulation - Glycogen Phosphorylase
Margaret A. Daugherty Fall 2003
Enzymes & Kinetics IV Regulation and Allostery ENZYME-SUBSTRATE INTERACTIONS THE LOCK & KEY MODEL Margaret A. Daugherty Fall 2003 A perfect match between enzyme and substrate can explain enzyme specificity
More informationTala Saleh. Ahmad Attari. Mamoun Ahram
23 Tala Saleh Ahmad Attari Minna Mushtaha Mamoun Ahram In the previous lecture, we discussed the mechanisms of regulating enzymes through inhibitors. Now, we will start this lecture by discussing regulation
More informationGENERAL THOUGHTS ON REGULATION. Lecture 16: Enzymes & Kinetics IV Regulation and Allostery REGULATION IS KEY TO VIABILITY
GENERAL THOUGHTS ON REGULATION Lecture 16: Enzymes & Kinetics IV Regulation and Allostery Margaret A. Daugherty Fall 2004 1). Enzymes slow down as product accumulates 2). Availability of substrates determines
More informationChapter 10. Regulatory Strategy
Chapter 10 Regulatory Strategy Regulation of enzymatic activity: 1. Allosteric Control. Allosteric proteins have a regulatory site(s) and multiple functional sites Activity of proteins is regulated by
More informationEnzymes: The Catalysts of Life
Chapter 6 Enzymes: The Catalysts of Life Lectures by Kathleen Fitzpatrick Simon Fraser University Activation Energy and the Metastable State Many thermodynamically feasible reactions in a cell that could
More informationBiochem sheet (5) done by: razan krishan corrected by: Shatha Khtoum DATE :4/10/2016
Biochem sheet (5) done by: razan krishan corrected by: Shatha Khtoum DATE :4/10/2016 Note about the last lecture: you must know the classification of enzyme Sequentially. * We know that a substrate binds
More informationPast Years Questions Chpater 6
Past Years Questions Chpater 6 **************************************** 1) Which of the following about enzymes is Incorrect? A) Most enzymes are proteins. B) Enzymes are biological catalysts. C) Enzymes
More informationLecture 6: Allosteric regulation of enzymes
Chem*3560 Lecture 6: Allosteric regulation of enzymes Metabolic pathways do not run on a continuous basis, but are regulated according to need Catabolic pathways run if there is demand for ATP; for example
More informationFIRST BIOCHEMISTRY EXAM Tuesday 25/10/ MCQs. Location : 102, 105, 106, 301, 302
FIRST BIOCHEMISTRY EXAM Tuesday 25/10/2016 10-11 40 MCQs. Location : 102, 105, 106, 301, 302 The Behavior of Proteins: Enzymes, Mechanisms, and Control General theory of enzyme action, by Leonor Michaelis
More informationEnzyme Regulation I. Dr. Kevin Ahern
Enzyme Regulation I Dr. Kevin Ahern Enzyme Regulation Mechanisms Enzyme Regulation Mechanisms 1. Allosterism Enzyme Regulation Mechanisms 1. Allosterism 2. Covalent Modification Enzyme Regulation Mechanisms
More informationAnas Kishawi. Zaid Emad. Nafez abu tarboush
24 Anas Kishawi Zaid Emad Nafez abu tarboush Hello everybody, this sheet is done according to Dr. Nafith s lecture so try to use his slides for the best understanding, and good luck. WAYS OF CHANGING THE
More informationEnzymes. Enzymes : are protein catalysts that increase the rate of reactions without being changed in the overall process.
Enzymes Enzymes Enzymes : are protein catalysts that increase the rate of reactions without being changed in the overall process. All reactions in the body are mediated by enzymes A + B E C A, B: substrate
More informationChapter 11: Enzyme Catalysis
Chapter 11: Enzyme Catalysis Matching A) high B) deprotonated C) protonated D) least resistance E) motion F) rate-determining G) leaving group H) short peptides I) amino acid J) low K) coenzymes L) concerted
More informationIntegration Of Metabolism
Integration Of Metabolism Metabolism Consist of Highly Interconnected Pathways The basic strategy of catabolic metabolism is to form ATP, NADPH, and building blocks for biosyntheses. 1. ATP is the universal
More informationFigure 1 Original Advantages of biological reactions being catalyzed by enzymes:
Enzyme basic concepts, Enzyme Regulation I III Carmen Sato Bigbee, Ph.D. Objectives: 1) To understand the bases of enzyme catalysis and the mechanisms of enzyme regulation. 2) To understand the role of
More informationStudent number. University of Guelph Department of Chemistry and Biochemistry Structure and Function In Biochemistry
University of Guelph Department of Chemistry and Biochemistry 19356 Structure and Function In Biochemistry Midterm Test, March 3, 1998. Time allowed, 90 min. Answer questions 120 on the computer scoring
More informationEnzymes: Regulation 2-3
Enzymes: Regulation 2-3 Reversible covalent modification Association with regulatory proteins Irreversible covalent modification/proteolytic cleavage Reading: Berg, Tymoczko & Stryer, 6th ed., Chapter
More informationCHAPTER 10: REGULATORY STRATEGIES. Traffic signals control the flow of traffic
CHAPTER 10: REGULATORY STRATEGIES Traffic signals control the flow of traffic INTRODUCTION CHAPTER 10 The activity of enzymes must often be regulated so that they function at the proper time and place.
More informationANSC 689 PHYSIOLOGICAL CHEMISTRY OF LIVESTOCK SPECIDS. Enzyme Kinetics and Control Reactions
Handout Enzyme Kinetics and Control Reactions ANSC 689 PHYSIOLOGICAL CHEMISTRY OF LIVESTOCK SPECIDS Enzyme Kinetics and Control Reactions I. Kinetics A. Reaction rates 1. First order (reaction rate is
More informationTheme 1 CONTROL OF ENZYME ACTIVITY
Theme 1 CONTROL OF ENZYME ACTIVITY Included in this section: Enzyme Activity: Control Notes in study material as well as slides used in class. Please use the study material provide as well as Matthews
More informationThe R-subunit would not the able to release the catalytic subunit, so this mutant of protein kinase A would be incapable of being activated.
1. Explain how one molecule of cyclic AMP can result in activation of thousands of molecules of glycogen phosphorylase. Technically it takes four molecules of cyclic AMP to fully activate one molecule
More informationAmino acids. Side chain. -Carbon atom. Carboxyl group. Amino group
PROTEINS Amino acids Side chain -Carbon atom Amino group Carboxyl group Amino acids Primary structure Amino acid monomers Peptide bond Peptide bond Amino group Carboxyl group Peptide bond N-terminal (
More informationLecture 34. Carbohydrate Metabolism 2. Glycogen. Key Concepts. Biochemistry and regulation of glycogen degradation
Lecture 34 Carbohydrate Metabolism 2 Glycogen Key Concepts Overview of Glycogen Metabolism Biochemistry and regulation of glycogen degradation Biochemistry and regulation of glycogen synthesis What mechanisms
More informationEnzymes Part III: regulation II. Dr. Mamoun Ahram Summer, 2017
Enzymes Part III: regulation II Dr. Mamoun Ahram Summer, 2017 Advantage This is a major mechanism for rapid and transient regulation of enzyme activity. A most common mechanism is enzyme phosphorylation
More informationChapter 3. Protein Structure and Function
Chapter 3 Protein Structure and Function Broad functional classes So Proteins have structure and function... Fine! -Why do we care to know more???? Understanding functional architechture gives us POWER
More informationENZYMOLOGY. Regulation of enzyme activity. P.C. Misra Professor Department of Biochemistry Lucknow University Lucknow
ENZYMOLOGY Regulation of enzyme activity P.C. Misra Professor Department of Biochemistry Lucknow University Lucknow-226 007 5-May-2006 (Revised 17-Aug-2006) CONTENTS Introduction Regulation of activity
More informationLecture 19: Review of regulation
Chem*3560 Lecture 19: Review of regulation What is meant by cooperative allosteric regulation? Positive cooperativity - characteristic is the sigmoidal binding/activity curve T-state has weaker affinity,
More informationPlasma membranes. Plasmodesmata between plant cells. Gap junctions between animal cells Cell junctions. Cell-cell recognition
Cell Communication Cell Signaling Cell-to-cell communication is essential for multicellular organisms Communicate by chemical messengers Animal and plant cells have cell junctions that directly connect
More informationChapter 23 Enzymes 1
Chapter 23 Enzymes 1 Enzymes Ribbon diagram of cytochrome c oxidase, the enzyme that directly uses oxygen during respiration. 2 Enzyme Catalysis Enzyme: A biological catalyst. With the exception of some
More informationENZYMES: CLASSIFICATION, STRUCTURE
ENZYMES: CLASSIFICATION, STRUCTURE Enzymes - catalysts of biological reactions Accelerate reactions by a millions fold Common features for enzymes and inorganic catalysts: 1. Catalyze only thermodynamically
More informationRegulation Through Conformational Changes
Regulation Through Conformational Changes These regulatory mechanisms (conformational changes) include: 1. Allosteric activation and inhibition. 2. Phoshorylation or other covalent modification. 3. Protein-protein
More informationCell Communication. Local and Long Distance Signaling
Cell Communication Cell to cell communication is essential for multicellular organisms Some universal mechanisms of cellular regulation providing more evidence for the evolutionary relatedness of all life
More informationUNIT 1: Introduction to metabolic regulation
UNIT 1: Introduction to metabolic regulation Prof K Syed Department of Biochemistry & Microbiology University of Zululand Room no. 247 SyedK@unizulu.ac.za Topics Metabolism Metabolism: Categories Important
More informationDEPARTMENT: Chemistry
CODE: CHEM-236 TITLE: Biochemistry Institute: STEM DEPARTMENT: Chemistry COURSE DESCRIPTION: Upon completion of this course the student will be able to recognize and draw the structure and state the nature
More informationProperties of Allosteric Enzymes
Properties of Allosteric Enzymes (1) An allosteric enzyme possesses at least spatially distinct binding sites on the protein molecules the active or the catalytic site and the regulator or the allosteric
More informationGeneral Principles of Endocrine Physiology
General Principles of Endocrine Physiology By Dr. Isabel S.S. Hwang Department of Physiology Faculty of Medicine University of Hong Kong The major human endocrine glands Endocrine glands and hormones
More informationIntroduction to metabolic regulation. Prof K Syed Department of Biochemistry & Microbiology University of Zululand Room no. 247
Introduction to metabolic regulation Prof K Syed Department of Biochemistry & Microbiology University of Zululand Room no. 247 SyedK@unizulu.ac.za Topics Metabolism Metabolism: Categories Important metabolic
More informationEffects of Second Messengers
Effects of Second Messengers Inositol trisphosphate Diacylglycerol Opens Calcium Channels Binding to IP 3 -gated Channel Cooperative binding Activates Protein Kinase C is required Phosphorylation of many
More informationCell Signaling part 2
15 Cell Signaling part 2 Functions of Cell Surface Receptors Other cell surface receptors are directly linked to intracellular enzymes. The largest family of these is the receptor protein tyrosine kinases,
More informationStudent number. University of Guelph Department of Chemistry and Biochemistry Structure and Function In Biochemistry
University of Guelph Department of Chemistry and Biochemistry 19356 Structure and Function In Biochemistry Midterm Test, March 3, 1998. Time allowed, 90 min. Answer questions 120 on the computer scoring
More information2018 Biochemistry 110 California Institute of Technology Lecture 11: Enzyme Regulatory Strategies
2018 Biochemistry 110 California Institute of Technology Lecture 11: Enzyme Regulatory Strategies 1. Aspartate Transcarbamoylase (ATCase) 2. Zymogen and Digestive Enzyme Regulation 3. Blood Clotting and
More informationMolecular Cell Biology Problem Drill 16: Intracellular Compartment and Protein Sorting
Molecular Cell Biology Problem Drill 16: Intracellular Compartment and Protein Sorting Question No. 1 of 10 Question 1. Which of the following statements about the nucleus is correct? Question #01 A. The
More informationBIOCHEMISTRY I HOMEWORK III DUE 10/15/03 66 points total + 2 bonus points = 68 points possible Swiss-PDB Viewer Exercise Attached
BIOCHEMISTRY I HOMEWORK III DUE 10/15/03 66 points total + 2 bonus points = 68 points possible Swiss-PDB Viewer Exercise Attached 1). 20 points total T or F (2 points each; if false, briefly state why
More information*For complete material(s) information, refer to
Butler Community College Science, Technology, Engineering, and Math Division Robert Carlson New Fall 2017 Implemented Fall 2018 COURSE OUTLINE Biochemistry Course Description CH 275. Biochemistry. 4 hours
More information3) How many different amino acids are proteogenic in eukaryotic cells? A) 12 B) 20 C) 25 D) 30 E) None of the above
Suggesting questions for Biochemistry 1 and 2 and clinical biochemistry 1) Henderson Hasselbalch Equation shows: A) The relationship between ph and the concentration of an acid and its conjugate base B)
More informationLipids and Membranes
Lipids and Membranes Presented by Dr. Mohammad Saadeh The requirements for the Pharmaceutical Biochemistry I Philadelphia University Faculty of pharmacy Membrane transport D. Endocytosis and Exocytosis
More informationBiol220 Cell Signalling Cyclic AMP the classical secondary messenger
Biol220 Cell Signalling Cyclic AMP the classical secondary messenger The classical secondary messenger model of intracellular signalling A cell surface receptor binds the signal molecule (the primary
More informationSYLLABUS MBMB/CHEM/BCHM 451b 2013 This class meets from pm every Tuesday and Thursday in Room 1059 (Auditorium) LS III.
1 SYLLABUS MBMB/CHEM/BCHM 451b 2013 This class meets from 12.35-1.50 pm every Tuesday and Thursday in Room 1059 (Auditorium) LS III. FACULTY P. M. D. Hardwicke, Room 210W, Neckers "C" Wing, Tel. 618-453-6469;
More informationSix Types of Enzyme Catalysts
Six Types of Enzyme Catalysts Although a huge number of reactions occur in living systems, these reactions fall into only half a dozen types. The reactions are: 1. Oxidation and reduction. Enzymes that
More informationSignal Transduction Cascades
Signal Transduction Cascades Contents of this page: Kinases & phosphatases Protein Kinase A (camp-dependent protein kinase) G-protein signal cascade Structure of G-proteins Small GTP-binding proteins,
More informationAP Biology Cells: Chapters 4 & 5
AP Biology Cells: Chapters 4 & 5 Multiple Choice Identify the choice that best completes the statement or answers the question. 1. The was the first unifying principle of biology. a. spontaneous generation
More informationEDUCATIONAL OBJECTIVES
EDUCATIONAL OBJECTIVES The lectures and reading assignments of BIS 2A are designed to convey a large number of facts and concepts that have evolved from modern studies of living organisms. In order to
More informationStudent Biochemistry I Homework III Due 10/13/04 64 points total (48 points based on text; 16 points for Swiss-PDB viewer exercise)
Biochemistry I Homework III Due 10/13/04 64 points total (48 points based on text; 16 points for Swiss-PDB viewer exercise) 1). 20 points total T or F; if false, provide a brief rationale as to why. Only
More informationLecture 15. Signal Transduction Pathways - Introduction
Lecture 15 Signal Transduction Pathways - Introduction So far.. Regulation of mrna synthesis Regulation of rrna synthesis Regulation of trna & 5S rrna synthesis Regulation of gene expression by signals
More informationScantron Instructions
BIOLOGY 1A MIDTERM # 1 February 17 th, 2012 NAME SECTION # DISCUSSION GSI 1. Sit every other seat and sit by section number. Place all books and paper on the floor. Turn off all phones, pagers, etc. and
More informationConcept 8.3: ATP powers cellular work by coupling exergonic reactions to endergonic reactions
Concept 8.3: ATP powers cellular work by coupling exergonic reactions to endergonic reactions A cell does three main kinds of work: Chemical Transport Mechanical To do work, cells manage energy resources
More informationSyllabus for BASIC METABOLIC PRINCIPLES
Syllabus for BASIC METABOLIC PRINCIPLES The video lecture covers basic principles you will need to know for the lectures covering enzymes and metabolism in Principles of Metabolism and elsewhere in the
More informationnumber Done by Corrected by Doctor Nayef Karadsheh
number 15 Done by BaraaAyed Corrected by Mamoon Alqtamin Doctor Nayef Karadsheh 1 P a g e Regulation of glycogen synthesis and degradation Regulation of glycogen synthesis and degradation involves two
More informationBIOL 4374/BCHS 4313 Cell Biology Exam #1 February 13, 2001
BIOL 4374/BCHS 4313 Cell Biology Exam #1 February 13, 2001 SS# Name This exam is worth a total of 100 points. The number of points each question is worth is shown in parentheses. Good luck! 1. (2) The
More informationPHRM 836 September 1, 2015
PRM 836 September 1, 2015 Protein structure- function relationship: Catalysis example of serine proteases Devlin, section 9.3 Physiological processes requiring serine proteases Control of enzymatic activity
More information5.0 HORMONAL CONTROL OF CARBOHYDRATE METABOLISM
5.0 HORMONAL CONTROL OF CARBOHYDRATE METABOLISM Introduction: Variety of hormones and other molecules regulate the carbohydrates metabolism. Some of these have already been cited in previous sections.
More informationExam 3 Fall 2015 Dr. Stone 8:00. V max = k cat x E t. ΔG = -RT lnk eq K m + [S]
Exam 3 Fall 2015 Dr. Stone 8:00 Name There are 106 possible points (6 bonus points) on this exam. There are 8 pages. v o = V max x [S] k cat = kt e - ΔG /RT V max = k cat x E t ΔG = -RT lnk eq K m + [S]
More information- Biosignaling: Signal transduction. References: chapter 8 of Lippincots chapter 1 3 of Lehningers
Basic concepts of Metabolism Metabolism and metabolic pathway Metabolic Map Catabolism Anabolism - Regulation of Metabolism Signals from within the cell (Intracellular) Communication between cells. - Biosignaling:
More informationCell Communication. Chapter 11. Biology Eighth Edition Neil Campbell and Jane Reece. PowerPoint Lecture Presentations for
Chapter 11 Cell Communication PowerPoint Lecture Presentations for Biology Eighth Edition Neil Campbell and Jane Reece Lectures by Chris Romero, updated by Erin Barley with contributions from Joan Sharp
More informationIntroduction. Biochemistry: It is the chemistry of living things (matters).
Introduction Biochemistry: It is the chemistry of living things (matters). Biochemistry provides fundamental understanding of the molecular basis for the function and malfunction of living things. Biochemistry
More informationHighlights Pentose Phosphate Pathway
Highlights Pentose Phosphate Pathway 1. The pentose phosphate pathway (PPP) is an interchange of metabolic pathways. 2. It is important to cells as a) an important source of NADPH, b) an important source
More informationCofactors and coenzymes. Reversible, irreversible, competitive, and noncompetitive inhibitors. Allosteric enzymes. Feedback inhibition.
Enzyme regulation Cofactors and coenzymes. Reversible, irreversible, competitive, and noncompetitive inhibitors. Allosteric enzymes. Feedback inhibition. Introduction The genome of a typical organism,
More informationIntroductory Biochemistry
BCH3023 Introductory Biochemistry BCH3023 Introductory Biochemistry Course Description: This course surveys the fundamental components of biochemistry. In this course, students will learn concepts such
More informationRegulation of glycogen degradation
Paper : 04 Metabolism of carbohydrates Module : 26 Principal Investigator Paper Coordinator Content Reviewer Content Writer Dr.S.K.Khare,Professor IIT Delhi. Dr. Ramesh Kothari,Professor UGC-CAS Department
More informationTuesday, Sept. 14, Is an enzyme a rigid system?
Tuesday, Sept. 14, Is an enzyme a rigid system? Early researchers thought of enzymes as rigid entities, recognizing their substrates the way a lock would recognize a key. Today's researchers, however,
More informationCarbohydrate Metabolism 2 Supplemental Reading
Carbohydrate Metabolism 2 Supplemental Reading Key Concepts - Overview of glycogen metabolism - Biochemistry and regulation glycogen degradation - Biochemistry and regulation of glycogen synthesis - Control
More informationCell Injury MECHANISMS OF CELL INJURY
Cell Injury MECHANISMS OF CELL INJURY The cellular response to injurious stimuli depends on the following factors: Type of injury, Its duration, and Its severity. Thus, low doses of toxins or a brief duration
More informationBiological Sciences 4087 Exam I 9/20/11
Name: Biological Sciences 4087 Exam I 9/20/11 Total: 100 points Be sure to include units where appropriate. Show all calculations. There are 5 pages and 11 questions. 1.(20pts)A. If ph = 4.6, [H + ] =
More informationBIOLOGY. Cell Communication CAMPBELL. Reece Urry Cain Wasserman Minorsky Jackson. Lecture Presentation by Nicole Tunbridge and Kathleen Fitzpatrick
CAMPBELL BIOLOGY TENTH EDITION Reece Urry Cain Wasserman Minorsky Jackson 11 Cell Communication Lecture Presentation by Nicole Tunbridge and Kathleen Fitzpatrick Cellular Messaging Cells can signal to
More informationCompanion to Biosynthesis of Ketones & Cholesterols, Regulation of Lipid Metabolism Lecture Notes
Companion to Biosynthesis of Ketones & Cholesterols, Regulation of Lipid Metabolism Lecture Notes The major site of acetoacetate and 3-hydorxybutyrate production is in the liver. 3-hydorxybutyrate is the
More informationThe MOLECULES of LIFE
The MOLECULES of LIFE Physical and Chemical Principles Solutions Manual Prepared by James Fraser and Samuel Leachman Chapter 16 Principles of Enzyme Catalysis Problems True/False and Multiple Choice 1.
More informationBiochemistry 1 ( ) Credit hours 2 Level 2 nd year Pre-requisite Biology I ( Coordinator/ Lecturer
The University of Jordan Faculty: Pharmacy Department: Biopharmaceutics and Clinical Pharmacy Program: Pharmacy Academic Year/ Fall Semester: 2013/14 Biochemistry 1 (1203251) Credit hours 2 Level 2 nd
More informationChapter 9. Cellular Signaling
Chapter 9 Cellular Signaling Cellular Messaging Page 215 Cells can signal to each other and interpret the signals they receive from other cells and the environment Signals are most often chemicals The
More informationReceptor mediated Signal Transduction
Receptor mediated Signal Transduction G-protein-linked receptors adenylyl cyclase camp PKA Organization of receptor protein-tyrosine kinases From G.M. Cooper, The Cell. A molecular approach, 2004, third
More informationPPP_glycogen_metabolism Part 2 الفريق الطبي األكاديمي. Done By: - Shady Soghayr
PPP_glycogen_metabolism Part 2 الفريق الطبي األكاديمي Done By: - Shady Soghayr لكية الطب البرشي البلقاء التطبيقية / املركز 6166 6102/ **How we get glucose-1-phosphate from glucose (source of glucose-1-
More informationFUNDAMENTALS OF BIOCHEMISTRY, CELL BIOLOGY AND BIOPHYSICS Vol. I - Biochemistry of Vitamins, Hormones and Other Messenger Molecules - Chris Whiteley
BIOCHEMISTRY OF VITAMINS, HORMONES AND OTHER MESSENGER MOLECULES Chris Whiteley Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, South Africa Keywords: phosphorylation, phosphorylase,
More informationSignal-Transduction Cascades - 2. The Phosphoinositide Cascade
Signal-Transduction Cascades - 2 The Phosphoinositide Cascade Calcium ion as a second messenger Tyrosine kinase and receptor dimerization scribd.com Faisal Khatib JU The Phosphoinositide Cascade Used by
More informationBCOR 011 Lecture 19 Oct 12, 2005 I. Cell Communication Signal Transduction Chapter 11
BCOR 011 Lecture 19 Oct 12, 2005 I. Cell Communication Signal Transduction Chapter 11 External signal is received and converted to another form to elicit a response 1 Lecture Outline 1. Types of intercellular
More information3/1/2011. Enzymes. Enzymes and Activation Energy. Enzymes Enzyme Structure and Action. Chapter 4 Outline. Enzymes
Free content 3/1/2011 Chapter 4 Outline Enzymes as catalysts Control of enzyme activity Bioenergetics Enzymes 4-2 4-3 Enzymes Enzymes - function as biological catalysts permit reactions to occur rapidly
More informationPROTEOMICS August 27 31, 2007 Peter D'Eustachio - MSB
PROTEOMICS August 27 31, 2007 Peter D'Eustachio - MSB 328 e-mail: deustp01@med.nyu.edu GOALS OF THIS SEGMENT OF THE COURSE Recognize the structures of the 20 amino acids; understand their properties as
More informationChapter 2 Transport Systems
Chapter 2 Transport Systems The plasma membrane is a selectively permeable barrier between the cell and the extracellular environment. It permeability properties ensure that essential molecules such as
More informationCell Communication. Chapter 11. PowerPoint Lectures for Biology, Seventh Edition. Lectures by Chris Romero. Neil Campbell and Jane Reece
Chapter 11 Cell Communication PowerPoint Lectures for Biology, Seventh Edition Neil Campbell and Jane Reece Lectures by Chris Romero Overview: The Cellular Internet Cell-to-cell communication Is absolutely
More informationIntracellular Compartments and Protein Sorting
Intracellular Compartments and Protein Sorting Intracellular Compartments A eukaryotic cell is elaborately subdivided into functionally distinct, membrane-enclosed compartments. Each compartment, or organelle,
More informationPublished on Second Faculty of Medicine, Charles University (http://www.lf2.cuni.cz )
Published on Second Faculty of Medicine, Charles University (http://www.lf2.cuni.cz ) Biochemistry Submitted by Marie Havlová on 8. February 2012-0:00 Syllabus of Biochemistry Mechanisms of enzyme catalysis.
More informationEnzymes. Enzyme. Aim: understanding the basic concepts of enzyme catalysis and enzyme kinetics
Enzymes Substrate Enzyme Product Aim: understanding the basic concepts of enzyme catalysis and enzyme kinetics Enzymes are efficient Enzyme Reaction Uncatalysed (k uncat s -1 ) Catalysed (k cat s -1 )
More informationIntegration of Metabolism 1. made by: Noor M. ALnairat. Sheet No. 18
Integration of Metabolism 1 made by: Noor M. ALnairat Sheet No. 18 Data :24/11/2016 SLIDE 2: Metabolism Consist of Highly Interconnected Pathways The basic strategy of catabolic metabolism is to form ATP,
More informationPropagation of the Signal
OpenStax-CNX module: m44452 1 Propagation of the Signal OpenStax College This work is produced by OpenStax-CNX and licensed under the Creative Commons Attribution License 3.0 By the end of this section,
More informationVets 111/Biov 111 Cell Signalling-2. Secondary messengers the cyclic AMP intracellular signalling system
Vets 111/Biov 111 Cell Signalling-2 Secondary messengers the cyclic AMP intracellular signalling system The classical secondary messenger model of intracellular signalling A cell surface receptor binds
More informationSarah Jaar Marah Al-Darawsheh
22 Sarah Jaar Marah Al-Darawsheh Faisal Mohammad Receptors can be membrane proteins (for water-soluble hormones/ligands) or intracellular (found in the cytosol or nucleus and bind to DNA, for lipid-soluble
More informationCELLS. Cells. Basic unit of life (except virus)
Basic unit of life (except virus) CELLS Prokaryotic, w/o nucleus, bacteria Eukaryotic, w/ nucleus Various cell types specialized for particular function. Differentiation. Over 200 human cell types 56%
More informationChapter 11. Cell Communication
Chapter 11 Cell Communication Overview: The Cellular Internet Cell-to-cell communication Is absolutely essential for multicellular organisms Concept 11.1: External signals are converted into responses
More informationBio 100 Serine Proteases 9/26/11
Assigned Reading: 4th ed. 6.4.1 The Chymotrypsin Mechanism Involves Acylation And Deacylation Of A Ser Residue p. 213 BOX 20-1 Penicillin and β-lactamase p. 779 6.5.7 Some Enzymes Are Regulated By Proteolytic
More informationPAPER No. : 16, Bioorganic and biophysical chemistry MODULE No. : 22, Mechanism of enzyme catalyst reaction (I) Chymotrypsin
Subject Paper No and Title 16 Bio-organic and Biophysical Module No and Title 22 Mechanism of Enzyme Catalyzed reactions I Module Tag CHE_P16_M22 Chymotrypsin TABLE OF CONTENTS 1. Learning outcomes 2.
More informationCell Communication. Chapter 11. Biology Eighth Edition Neil Campbell and Jane Reece. PowerPoint Lecture Presentations for
Chapter 11 Cell Communication PowerPoint Lecture Presentations for Biology Eighth Edition Neil Campbell and Jane Reece Lectures by Chris Romero, updated by Erin Barley with contributions from Joan Sharp
More informationnumber Done by Corrected by Doctor Faisal Al-Khatibe
number 24 Done by Mohammed tarabieh Corrected by Doctor Faisal Al-Khatibe 1 P a g e *Please look over the previous sheet about fatty acid synthesis **Oxidation(degradation) of fatty acids, occurs in the
More information