CHEM 3391B TERM TEST - Winter March 8 Elborn Collge EC2155 (EC 2155) 10:30 12:15 SYLLABUS

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1 CHEM 3391B ERM ES - Winter March 8 Elborn Collge EC2155 (EC 2155) 10:30 12:15 SYLLABUS he erm est content will be weighted approximately 90% Lecture Material and 10% Presentation Executive Summaries (see below) All lectures - up to hursday 1 st March 2018 (all of the Bio unit from this week). Questions taken from the Executive Summaries of the Presentation #1 and #2 - need to know major points from 4 Executive Summaries of each presentation as outlined. (Yes, your two are part of the four each time). here will be no Periodic able provided. Bring a calculator. Pencils and coloured pens helpful - just not "red". You will need to know the Periodic able entries up to Kr. riads involving Cu and Zn needed. Also, Pb, Bi. Place in the table and electronic configurations and common (bio) oxidation states. Hard/soft examples. he goals of this instructor are that by attending the lectures and reading the notes you will have a very good grasp of the material. he essence of this first part is remembering that providing examples is important. And those examples need to have some detail - the Compare & Contrast ideas. So, reading from the beginning and checking you follow the arguments is a very good first step. I try not to ask questions about small points (but my big point might be your small point). (A) Introduction - lots of detail. Check the end of the unit for key points (B) Metals - part 1 Check: metals - essential; toxic; metallodrugs; etc (C) Periodic able basics part 2 All the inorganic material; binding constants; be able to calculate H/S/G/K given the other information. Amino acids that bind metals; heme b; (= Greek delta) () Bio - Note several sections not included - need to check your notes. Be able to discuss the role of specific metal-binding amino acids and draw the structures of the metal-binding amino acids protein structure etc In Kaim.. p 1-116; but you should thumb through the rest noting may be images and paragraphs we have covered - - I liked the cycles and heme protein examples that we saw last week.-- there's a very nice section on p 200 about Cyt oxidase - heme a. Zinc starting on p we have covered in part already. Really a read through would be useful. But - my questions and their answers come from the notes and what I have said in class. 3391B-2018-ermest-syllabus-2018march8-rev-18-a.docx Page 1 of 1

2 o be included for sure from 2018 MarkedUp pdfs INRO/INORG/BIO O2 binding to myoglobin heme Broadly defined, bioinorganic chemistry is the study of inorganic elements, with an emphasis on metals, in living systems. 1. Which elements are necessary for life? 2. How about their chemical speciation? 3. What are their physiological roles? 4. What are their mechanisms of action? 5. How did we evolve to use those elements? 6. Why are some metals toxic? 7. Can metals be used therapeutically? Name 4 metals with greater than about 1 g in the average 70 kg Man Give an example of two element that have critical physiological role but its abundance (is far less than 1 g in the typical 70kg man (Se/Co/ highlighted What is an essential element? What Is an Essential Element? In order for an element to be classified as essential, it must satisfy all of these criteria for essentiality: 1) When the element is removed from the diet, a physiological or structural abnormality appears. 2) he addition of the element to the diet restores or relieves the abnormality. 3) he element has a specific biochemical function even if the function of the element is not fully understood, as in the case of many ultratrace elements. 4) he element follows a dose-response curve. -- see later. 1

3 5) Essential elements can be classified according to either the amount present in the body or the dietary requirement (recommended daily intake/allowance): 6) Bulk elements 7) Major elements / macronutrients / macrominerals 8) Minor elements / micronutrients / microminerals race elements Ultratrace elements Name 4 essential metals (not Na/K/Ca) 4 toxic metals Cd, Hg, Pb, As, Cr6+** Mg, e, Co, Zn,Cu, Mn, Mo, Cr, Ni, 4 therapeutically important metals Li, Cu, Ag, Au, Pt, Bi What is the class and give an example --- Oxidoreductase: Oxidoreductases catalyze oxidation reduction reactions. At least one substrate becomes oxidized and at least one substrate becomes reduced. Also the transfer of H and O atoms. Alcohol dehydrogenase - Zn (x2); catalases (e-heme x4); xanthine oxidase (Mo & es) (xanthine to uric acid) 2) ransferase What is the difference between a Metalloenzyme and a metal-activated enzyme? Explain 4 differences and provide an example for each of the metal and the enzyme Metalloenzymes Metalloenzymes metal is firmly bound metal to protein ratio is constant metal to enzyme activity ratio is constant metal is unique no enzyme activity without metal Examples of metalloenzymes: 2

4 superoxide dismutase (Zn and Cu) carboxypeptidase A (Zn) CPA carbonic anhydrase (Zn) CA cytochrome oxidase (e and Cu) CcOx xanthine oxidase (Mo, Co and e) Metal-activated enzymes metal is reversibly bound metal to protein ratio is variable metal to enzyme activity ratio is variable metal is not necessarily unique enzyme activity may continue without metal Examples of metal-activated enzymes creatine kinase (Mg, Mn, Ca or Co) glycogen phosphorylase kinase (Ca) salivary and pancreatic alpha-amylases raw the hemec in myoglobin - being careful about the peripheral decoration. What is the explanation for the change between the hemes in oxy- and deoxyhemoglobin? he key amino acid in myoglobin that binds to the heme iron is which amino acid and which sequence number? (His 93) ioxygen can be reduced to water list the intermediate species. Which is the most deadly to the cell? (O2 - - superoxide) Please attempt the calculation, then choose the best answer from those given and finally select the submit button to see whether you were correct. Calculate the entropy changes at 25 C, for the following reactions: Zn2+ + 2NH3 <=> [Zn(NH3)2]2+ ΔH = kj mol-1 and log10 β2 = 5.01 Zn2+ + en <=> [Zn(en)]2+ ΔH = kj mol-1 and log10 β = 6.15 ( R=8.314 JK-1mol-1) 3

5 A) -190, -214 JK-1mol-1 B) 1.9, 25.2 JK-1mol-1 C) -5.3, -4.1 JK-1mol-1 ) 23, 300 JK-1mol-1 None of these, or I don't know. Which of the following amino acids binds preferentially to softer metals? Give a list Know the metal binding amino acids and their structures raw the R group for Cys, His and yr 4

6 About how many amino acids are required for normal physiological mammalian chemistry? 20 How many have to be in the diet.? 9-11 List 4 stabilization energies that hold the 30 structure together - Note 4 types of bio-interaction plus 1 =5) i) hydrogen bonding, ii) hydrophobic interactions between hydrophobic side chains (always very organic, not ionic induced dipoles); (and van der Waals forces) iii) ionic bonds or electrostatic bonds; iv) disulfide bridges the strongest because these are the only true covalent bond that cross-links the protein - a major component of tertiary structures (and also quaternary structures) and (v) bonds to metals also covalent bonds but can be displaced by competition raw a diagram that explains briefly what a molecular chaperone isa molecular chaperone is 5

7 Student Number: with answers Name of Student: he University of Western Ontario Chemistry 3391B - example exam questions not everything was covered the same this year s answers and typos corrected as used HE WRIEN PAR O HIS ES includes material similar to this current year the format of the exam is NO necessarily the same. 1. (4 marks) Complete the following: i) Arrange K +, Na +, Mg 2+, Cl by size smaller on the LHS ii) Write out the triad of elements: with Cu as the lightest with Zn as the lightest iii) Write out the six BLOCK elements before Zn: Mg 2+ <Na + < K + < Cl Cu Ag Au Zn Cd Hg he set includes Cr, Mn, e, Zn Co, Ni, Cu, Zn (2 marks) Which statements are RUE concerning significant human exposure to mercury in any form from eating livers of cattle from eating shellfish from drinking contaminated water from the dust from old paint from preservatives used on wood from vaccines from dental amalgams from fungicides used on grain 2. Identify all of the following metal(s) that in some form is/are known to cause neurological disease at low exposure levels? (WRIE ALL CORREC LEERS ON HE ANSWER SHEE OR QU. 10) A) Na B) Ca C) Hg ) Mn E) Cd ) Zn Identify all of the following that are known to be essential elements for human life. (LIS ALL) A) Na B) Cr C) Hg ) Mn E) Cd ) Zn 5. Which single protein of the following transports e in the blood stream? A) erritin B) Myoglobin C) Carbonic Anhydrase ) ransferrin E) Cytochrome C 6. In a typical 70 kg human there is less than 1 gram (1000mg) for which metals? (Circle the letter of RUE answers and write all these letters on to the answer sheet provided) A) Ca B) Cr C) Pb ) Mn E) e ) Cu 7. How many amino acids are required by humans? A) 15 B) 20 C) 30 ) 45 B 8. How many must be part of our diet? A) None B) All C) 5 ) 10 E) he chlorophyll molecule has which metal bound to the ring? A) Mn B) e C) Zn ) Ca E) Mg ) Co E 10. Zinc is: i) only present in ultratrace amounts in a typical 70 kg person ii) available in many common foods in the diet, especially meat, eggs, and seafoods iii) necessary for development and functioning of the brain iv) deficiency is unusual unless there is liver disease present v) high zinc in the diet is dangerous because zinc can be toxic A) all B) ii, iii, iv, only C) i, ii, iii, iv, only ) i, v only E) i, iv, v only AB C,,,,,, Ans B C B

8 Chemistry 3391B sample exam questions SUEN NAME: Page 2 of Significant human lead exposure is from? i) water pipes ii) paint in old houses iii) cigarette smoke iv) smelting v) burning coal vi) preservatives on wood A) all B) i, ii, vi only C) iii, iv, v, vi only ) ii, iii, iv only E) i, ii, iv only 12. If the Ksp of HgS is 10-53, calculate the volume of water (in L) at ph7 containing one Hg 2+ ion (Avogadro s Number = 6.02 x ). A) Less than 1.0 ml B) 1.0 to 100 ml C) 100 ml to 2 L ) 2 L to 20 L E) 20 L to 1000 L Which of the following is a potential source of metal poisoning specifically discussed in class? E E A) Some vibrant pottery glazes/ colors contain high levels of toxic cobalt B) Many fertilizers are sourced from minerals laced with aluminum C) Some children s toys can contain dangerous amounts of mercury ) Some candies have been identified with high levels of toxic copper E) Some jewelry has recently been found to contain high levels of cadmium 15. he electronic configuration of e 3+ includes: A) 4s 2 3d 3 B) 4s 1 3d 4 C) 4s 0 3d 6 ) 4s 0 3d 5 E) 4s 0 3d How many of the following statements is/are rue concerning the role of Iron, e, in biology? i. When the atmosphere became oxygen rich the insoluble iron salts from the original rocks dissolved and the iron then entered into the evolutionary chain ii. Soluble iron salts are still plentiful in the environment so modern organism still use iron for many functions iii. Iron can usually be replaced by other metals because it is a transient metal in enzymes iv. Iron is only used in the heme protein myoglobin and hemoglobin v. In a healthy adult body, iron is the most abundant d block metal A) Only 1; B) only 2; C) only 3; ) only 4; E) all Which statement(s) is/are RUE concerning the ligand esferrioxamine B? (i) It binds using a combination of N and S donor atoms (ii) It binds only with O donor atoms (iii) It binds only with S donor atoms (iv) It binds using a total of 4 O and 2 N donor atoms (v) Is a very Hard ligand (vi) Predicted to bind very strongly to e 3+ A A) (i) and (v) only; B) (i), (iv), (v) and (vi) only; C) (ii) only; ) (ii), (v) and (vi) only; E) (iv), (v), and (vi) only 18. Which list contains below contains only HAR ligands? A) CYS, ME, and CO B) EA 4, CYS, and HIS C) EA 4, YR, and CN ) YR, EA 4, and GLUAMIC ACI E) 3 PO 4, Se 2 and 2 CO B-Sample-ermest-Questions & Answers.docx Page 2 of 3

9 Chemistry 3391B sample exam questions SUEN NAME: Page 3 of Which list below only contains metals that are considered HAR metals when they have one of their usual their oxidation state(s)? A) Cd and Hg B) Na, K, and Ca C) Cu, Co, and Zn ) Ca, Mg, and Au E) Na, K, and Pt 20. Using H for Hard, S for Soft & I for Intermediate, identify the requested pairs (HH, SS, SH, HS, IH, IS, HI, or SI as appropriate) answer this and the following question (the metals will have their usual oxidation state) Which of the following pairs are SS? (i) Ca & CYS (ii) HgCH3 + & CYS (iii) Ca & MEHIONINE (iv) e(2+) & HIS (v) Hg(2+) + & YROSINE A) (i), (ii), (iii) only; B) (ii), (v) only; C) (i), (iii), (iv), (v), only; ) (iii), (iv), (v) only; E) (ii) only 21. he electronic configuration for Mn(3+) is: (Note: the superscripted numbers are left on the line to aid clarity so read 3d4 3s0 as 3d 4 4s 0 ) A) [Ar] 3d4 4s0 B) [Ar] 3d3 4s2 C) [Ar] 3d5 4s0 ) [Ar] 3d2 4s2 E) [Ar] 3d2 4s0 22. Which statement(s) is/are correct concerning the molecule that is the basis for heme (PPIX)? (i) here is a hydrophobic side and a hydrophilic side (ii) When drawing, one needs to place four (4) methyl groups somewhere along the perimeter of the ring. (iii) When drawing, one needs to place two vinyl on the perimeter adjacent to each other (iv) When drawing, one needs to place 2 propionic acid groups on the perimeter adjacent to each other.. (v) here are eight (8) places that the ring can be modified on the pyrrole perimeter but two (2) are not substituted and remain protons. B HS SS HS II SH E A B A) All; B) (i), (ii) and (iv) only; C) (i), (ii), (iii), and (iv) only; ) (i), ii), and (iii) only; E)(i) and (ii) only 3391B-Sample-ermest-Questions & Answers.docx Page 3 of 3