In the 1960s, the drug thalidomide was prescribed to pregnant women to treat morning sickness. However, thalidomide caused severe limb defects in the children of some women who took the drug, and its use for morning sick- ness was discontinued. It is now known that thalidomide was administered as a mixture of two stereoisomeric compounds, one of which relieved morning sickness and the other of which was responsible for the birth defects. What are stereoisomers? Why might two such closely related compounds have such different physiological effects?

A peptide composed of 40 amino acids (aa) was isolated from the venom of the Gila Monster(Heloderma suspectum, then submitted to various biochemical and chemical treatments.1) After a treatment with a highly specific chymotrypsin, four peptides were generated:- peptide A (6 aa)- peptide B (16 aa)- peptide C (3 aa)- , and peptide D (15 aa)2) Treatment with carboxypeptidases A or B resulted in the release of:- phenylalanine for peptides A and B- tryptophan for peptide C- glycine for peptide D and the 40 amino acids venom peptide3) One cycle of Edman degradation either for peptide A or for the 40 amino acidspeptide gave the exact PTH derivative indicated below: 4) The 40 amino acids peptide treated with Asp-N endopeptidase followed by massspectrometry MS/MS revealed the following composition:- two molecules of glutamic acid,- various peptides indicated below sorted by masses:HG,DLSKQM,EGTFTS,EAVRLFI,EWLKNGGPSSGAPPPSG Information- Chymotrypsin (endopeptidase) hydrolyzes peptide bonds on…

Glucose-1-phosphate has a ΔG°′ value of −20.9 kJ/mol, whereas that for glucose-6-phosphate is −12.5 kJ/mol. After reviewing the molecular structures of these compounds, explain why there is such a difference in these values.

What is an oligopeptide? How is it different from a polypeptide?