. (a) Explain the biochemical basis for the fact that one can synchro- nize cell populations þy treating them with deoxythymidine. (b) Explain the apparent paradox that dATP at low concentrations is an activator of ribonucleotide reductase, whereas at higher concen- trations it becomes inhibitory.
Q: Some of the following four amino acids : alanine, arginine, histidine, aspartic acid would provide a…
A: Acid-Base Catalysis is involved in the reaction mechanisms that requires the transfer of a proton…
Q: Under certain conditions, peptide bond formation rather than peptide bond hydrolysis is…
A: Peptide bond formation- A peptide bond is a chemical bond formed between two molecules when the…
Q: ctabolism in the to particular experiment. It is known that potatocs practically do not contain…
A: There are various verities of food that we consume contain nutrients, fatty acids , carbohydrates ,…
Q: 6-Diazo-5-oxonorleucine (DON) irreversibly inhibits glutamine-dependent amidotransferases. CH=N+=N-…
A: Introduction: DON is a water-soluble glutamine enemy which was separated initially from Streptomyces…
Q: TFQFPFAEQL EKVAEQFPTF QILNEEGEVV NEEAMPELSD EOLKELMRRM : (amino h (amino) (amino i (amino amg…
A: These six amino acid residues are split between two subunits. Together, they form a BASIC tunnel…
Q: What is formed when serine 195 acts as a nucleophile on the carbonyl carbon of the peptide bond?…
A: A catalyst is a molecule that can increase the rate of a chemical reaction. The amount of catalysts…
Q: Write the mechanism (in detail) for the conversion of aspartate and carbamoyl phosphate into N -…
A: Aspartate carbamoyl transferase helps in the initial step of biosynthetic pathway of pyrimidine…
Q: The catalytic mechanism of bovine pancreatic RNase A relies upon acid-base catalysis involving the…
A: Bovine pancreatic RNase is a nuclease Enzyme that catalyses the cleavage of RNA. The protein…
Q: Serine Proteases, such as chymotrypsin, contain Ser/Asp/His as a catalytic triad (i.e. three…
A: Enzymes are a class of proteins except for ribozymes (class of RNA) that enhance the rate of…
Q: 16. This figure from Foundations should look familiar. Which protein is shown here? catalytic triad…
A: Every enzyme has its own active site where substrate molecules bind and undergo a chemical reaction.…
Q: 1 Specify the role each of the following amino acids play within the crystal structure and/or active…
A: "Since you have asked multiple questions, we will solve the first question for you. If you want a…
Q: Describe how the concentrations of the four deoxyribonucleotides are balanced by ribonucleotide…
A: Introduction: Ribonucleotide reductase (RNR) is a key enzyme that mediates the synthesis of…
Q: A)How could the sequence of Ala-Met-Thr be distinguished from that of Thr-Ala-Met by tandem ESI-MS?…
A: A polypeptide is a polymer of amino acids. The sequence of a polypeptide is written from the…
Q: Which of the following regulatory mechanisms will specifically inhibit pyrimidine synthesis (and not…
A: De novo pathway and salvage pathways are two pathways used for nucleotide biosynthesis. In the…
Q: If you were to mutate Ser195 in the catalytic triad of chymotrypsin to another amino acid, which…
A: A change in the nucleotide sequence is referred to as a mutation. A mutation in the nucleotide…
Q: What is the evidence that aspartate transcarbamoylase (ATCase) effects catalysis primarily by…
A: Aspartate carbamyl transferase or astartate transcarbamoylase, transfers a carbamoyl group from…
Q: Draw the first tetrahedral intermediate of the chymotrypsin mechanism (a single structure, no arrows…
A: Chymotrypsin is the hydrolyase enzyme which catalyzes the hydrolysis of peptide bonds of proteins…
Q: In the "biochemical assay of b-galactosidase activity", what is o-nitrophenyl-b-D-galactosidase…
A: Introduction The lac operon model was first proposed by F. Jacob and J. Monod. Lac operon an…
Q: under certain conditions alpha helical bundles can form and can facilitate protein insertion into…
A: Integral membrane proteins fold into their active conformations in a complex milieu dictated by the…
Q: From the complete oxidation of glucose (glucose → 6CO2), how many total nucleotide triphosphates are…
A: Glucose is metabolized through the glycolytic pathway to yield energy in the form of ATP and NADH.…
Q: ubiquitin attaches to proteins via many biochemical reactions, please explain how this attachment…
A: Ubiquitin is a highly conserved 76-residue monomeric protein found in eukaryotes. It is found in…
Q: Provide a simple sketch of the covalent intermediate likely to form between active site serine…
A: DPCC: Diphenylcarbamyl chloride has two phenyl group attached to carbamyl chloride. Serine Protease:…
Q: 6.3.7 Activity (1) List and briefly explain four methods of studying an E-S complex. (2) (a) Which…
A: When an enzyme comes into perfect contact with its substrate, a transient molecule called the enzyme…
Q: The catalytic mechanism of bovine pancreatic RNase A relies upon acid-base catalysis involving the…
A: Bovine pancreatic RNase A catalyzes the hydrolysis of phosphodiester bond of the RNA.
Q: Define the term thiolytic cleavage. In what biochemical process does it occur?
A: A reaction in which a bond to a sulfur atom is broken is known as the thiolytic cleavage. In the…
Q: Describe the path for the synthesis of TTP from UTP.
A: Nucleic acids are biomolecules that form the building blocks for DNA and RNA molecules. They contain…
Q: Consider applying biocatalytic reduction with carrots to the following two ketones: tert-butyl…
A: Introduction :- Bio-catalysis is the process of using natural substances like- enzymes for…
Q: 22. Describe the Induced fit of Hemoglobin, Hb (enzyme-like protein) which has quarternary structure…
A: The induced fit model is a model for the interaction of enzymes with substrates. It states that only…
Q: . (a) Explain the biochemical basis for the fact that one can synchro- nize cell populations by…
A: dATP is a nucleotide used in cells for DNA synthesis, as a substrate of DNA polymerase. It is…
Q: Carbohydrates can play important roles by modulating interactions between proteins. For example,…
A: Thrombin (coagulation factor II) is a serine protease that plays a vital role in hemostasis and…
Q: Tissues that are unable to produce nucleotides de novo depend on ____________________ to maintain an…
A: Biomolecules are organic molecules present in living organisms. Nucleic acids are one such…
Q: What is the first thing that must occur in order for the catalysis of the peptide bond to begin.…
A: Macromolecules are large organic molecules composed of thousands of covalently connected atoms and…
Q: Provide the mechanism for step 2 of the biological formation of geranyl diphosphate (A') are…
A: Coupling of two Isopentenyl pyrophosphate molecules gives geranyl pyrophosphate or geranyl…
Q: What is the catalytic triad of chymotrypsin? Describe the mechanism of chymotrypsin in cleaving a…
A: Chymotrypsin is a digestive enzyme component of pancreatic juice acting in the duodenum, where it…
Q: The enzyme creatine kinase catalyzes the ATP-dependent phosphorylation of creatine. Propose a…
A: Introduction: Creatinine is the waste product formed in muscle from a high-energy storage compound…
Q: Azaserine inhibits amidotransferases. State the purine precursor that resembles azaserine. Which…
A: Cancer is the abnormal growth and multiplication of normal cells. Cancer cells divide rapidly.…
Q: Serine esterase contains a catalytic triad at its active site. Which amino acid in serine esterase…
A: Serine esterase contains three amino acids, His 57,Ser 195 and Asp 102.These three residues form a…
Q: . Phosphatidylserine (PS) is considered to be an intermediate in the biosynthesis of…
A: Phosphatidylserine : It is fatty substance produced in the body that covers and protects every cell…
Q: Describe the experimental evidence that supports lysozyme’s catalysis by acid– base catalysis,…
A: Lysozyme, also known as muramidase or N-acetylmuramide glycanhydrolase, is an antimicrobial enzyme…
Q: . Explain why DNA is stable in the presence of alkali (0.3 M KOH), while RNA is quantitatively…
A: DNA and RNA act as genetic material in various organisms. DNA contains four bases-adenine, guanine,…
Q: Explain the role of β-galactosidase ?
A: Introduction: Genetic expression in bacteria is coordinated by an operon. When Jacob and Monod…
Q: Draw the mechanism for the serine protease catalyzed hydrolysis of a diglycine peptide.
A: The serine protease is the class of protease enzyme, which is known to catalyze the hydrolysis of…
Q: Some bacteria contain three different forms of aspartokinase, each with its own mode of regulation.…
A: Aspartokinase is an enzyme which catalyzes the phosphorylation of aspartate, an amino acid. It…
Q: Draw a stepwise mechanism for conversion of radical intermediate A to prostaglandin PGG2.
A: Arachidonic acid is the precursor of prostaglandin. The enzyme cyclooxygenase(cox) catalyze the…
Q: What is the purpose of the NaKATPase in a mammalian cell?
A: A phospholipid bilayer integrated with proteins forms the plasma membrane. It provides a durable…
Q: A peptide with the primary structure Lys–Arg–Pro– Leu–Ile–Asp–Gly–Ala is sequenced by the Edman…
A: Given Values: Efficiency of the edman cycle = 96% or 0.96 The second time it needs to be assumed =…
Step by step
Solved in 3 steps
- Allosteric Regulation of Ribonucleotide Reductase by ATP and Deoxynucleotides Describe the underlying rationale for the regulatory effects exerted on ribonucleotide reductase by ATP, dATP, dTTP, and dGTP.. (a) Explain the biochemical basis for the fact that one can synchro- nize cell populations by treating them with deoxythymidine. (b) Explain the apparent paradox that DATP at low concentrations is an activator of ribonucleotide reductase, whereas at higher concen- trations it becomes inhibitory.Briefly describe the induced-fit conformational change when hexokinase binds its substrate.
- Describe the mechanism of action of 1 cycle of the ubiquitin (Ub) ligase system. Describe how the E1, E2 and E3 ligases work to covalently link Ub to the target protein, including which uses an energy source (and how), and the operative amino acids on the enzymes, Ub and target proteinTPCK and TLCK are irreversible inhibitors of serine proteases. One ofthese inhibits trypsin and the other chymotrypsin. Which is which? Explainyour reasoning. Suggest the effects of each of the following mutations on the physiologicalrole of chymotrypsinogen:(a) R15S(b) C1S(c) T147SFrom the complete oxidation of glucose (glucose → 6CO2), how many total nucleotide triphosphates are yielded (be sure to deduct payback) as part of substrate level phosphorylation?
- (i) Describe the mechanism of chymotrypsin in cleaving a peptide bond, highlighting the roles of the catalytice triad for the two phases of the catalytic reactions. Explain the significance of the oxyanion hole for the catalysis. (ii) All serine proteases contain the catalytic triad and these amino acids are positioned in the exact same conformation. Since this is true, why do trypsin and chymotrypsin have such different substrate specificity? What features of the enzyme allow for this situation?Synthesis of the purine nucleotides AMP andGMP proceeds by a branched pathway starting with ribose5-phosphate (R5P), as shown schematically in FigureQ3–4. Using the principles of feedback inhibition, proposea regulatory strategy for this pathway that ensures an ade-quate supply of both AMP and GMP and minimizes thebuildup of the intermediates (A–I) when supplies of AMPand GMP are adequate.. In Figure 6-11,a. in view of the position of HPA oxidase earlier in thepathway compared to that of HA oxidase, would youexpect people with tyrosinosis to show symptoms ofalkaptonuria?b. if a double mutant could be found, would you expecttyrosinosis to be epistatic to alkaptonuria?
- Describe how the concentrations of the four deoxyribonucleotides are balanced by ribonucleotide reductase.Will rate ASAP Which of the following amino acid residues would not provide a side chain for acid-base catalysis at physiological pH? (Assume pK values of each amino acid are equal to the pK value for the free amino acid in solution.) I. leucine II. lysine III. aspartic acid IV. histidine A) I, II, III B) I, II C) I D) II E) I, IIIChymotrypsin, trypsin, and elastase all share the same catalytic mechanism, but have different specificities. (a) These proteases are considered serine proteases because the active sites contain serine, histidine and aspartate. Describe the roles that each of these amino acid residues play in hydrolyzing protein substrates. (b) The active site pockets of chymotrypsin, trypsin, and elastase are shown in the image below. Based on the image, which side chain of the amino acids would they prefer to cleave respectively, Ala, Arg, or Trp? Explain your answers. Val 216 Val 190 Asp 189 Chymotrypsin Trypsin Elastase