Question

b) Beekinin is an oligopeptide released by blood plasma globulins in response to a Bee sting. It is a very potent pain-causing agent. Its molecular formula is Arg2, Gly, Phe, Pro3, Ser, Cys, Leu. The use of DNFB and carboxypeptidase show that both terminal residues are arginine. Partial acid hydrolysis of Beekinin gives the following di- and tripeptides. Gly. Phe + Pro.Ser + Cys. Leu + Ser.Cys + Leu.Arg + Arg.Gly + Phe. Pro + Pro. Pro. Pro What is the amino acid sequence of Beekinin? (6)

Answer 1

peptideare we get exminal as pra from the use of DNEB we get N-terminal as hog . with the use of carboxypeptidease we get e so our sequence would Arg annan Ang Molecular formula guver to that there are 2 Arg which already used as terminus (both end], I gly, 1 Phe, 3 Pro, 1. Ser, 1 cys, 1 leu upon hydrolysis me got fragments like Gly- Phe ; Pro-ser, as you ser, cys , et The-Pro , Pro-fro - Poo from the fragment we need to prefare the sequence - Go toe, Ser, gps, 40-Arg, Argogle as seen from yoom to agment to Ang-Gly. There Arg ů N terminus and . our oligopeptide contain Arg as N terminus so sequence would begin as 1. Arg-Gly is present, so the will be glycine my z attached to Arg gly-phe - similarly o nt larg Bus nens amino acid would be Next we have Gly-Phe, sanie only & glycine sp The next amino acid attached to Arg - gly-Phe from fragment Phe - Pro we get next amire acid as Poo and requence a Arg Gly-Phe-loo , there are 3 Proline units and from Reagment to obtained (Pro-Pro-Pro), the next two amino acid will be Pro-lo, sequence would become ing-gly-Phe- Phe-Pro-tro-fro similarly again from fragment (Pro-ses) our next be ser; from fragment (to - Cys) our Cys, sequence becomes - Ang-Glyphe - Pro-fro-bro-ser-gs- in fragment in Cry - deu, next amino aced would seu and the east fragment deu-Arg would Corroborates that dog was also our ve-terminal. so the requered sequence is Arg - Gy-the-ho-Pro -lao-ser-45-den - Horg Ics Scanned with CamScanner from hot fragment Leu-Arg would end the sequence which also