draw the ionized polypeptide made of Phe-Asp-Cys-Arg at pH 7
An octapeptide contains the following amino acids: Met, Thr, Cys, Asp, Phe, Arg, Glu, Gln. Carboxypeptidase treatment of the octapeptide forms Asp and a heptapeptide. Treatment of the octapeptide with Chymotrypsin forms forms two tetrapeptides, A and B. Treatment of A with Trypsin yields two dipeptides, C and D. Edman degradation cleaves the following amino acids from each peptide: Cys (octapeptide), Cys (A), Gln (B), Cys (C), Glu(D). Partial hydrolysis of tetrapeptide B forms Gln-Thr in addition to other products....
An octapeptide contains the following amino acids: Met, Thr, Cys, Asp, Phe, Arg, Glu, Gln. Carboxypeptidase treatment of the octapeptide forms Asp and a heptapeptide. Treatment of the octapeptide with Chymotrypsin forms forms two tetrapeptides, A and B. Treatment of A with Trypsin yields two dipeptides, C and D. Edman degradation cleaves the following amino acids from each peptide: Cys (octapeptide), Cys (A), Gln (B), Cys (C), Glu(D). Partial hydrolysis of tetrapeptide B forms Gln-Thr in addition to other products....
What peptides are expected to be produced when an unknown hormone (Cys−Ala−Phe−Met−Gly−Asp−His−Arg−Ala−Cys−Lys−Pro−Val) is cleaved by: a) trypsin b) cyanogen bromide c) thermolysin
If the peptide Cys-Gly-Phe-Lys-Ala-Arg-Asp-Gly is subjected to acid hydrolysis, what will be the products? peptide fragments fragments of amino acids individual amino acids
Styles A decapeptide has the following amina acid composition: Arg. Asp, Gly, Leu, Lys, Met, Phe, Ser. Trp, and Val Reacting the native peptide with FDNB and then hydrolyzing released 2.4- dinitrophenylvaline. Brief incubation of the native peptide with carboxypeptidase yielded free Leu. Incubation with cyanogen bromide yielded two fragments: a tetrapeptide with composition Met, Phe, Ser, and Val, and a hexapeptide. The hexapeptide yielded 2.4- dinitrophenylglycine. Proteolytic cleavage by trypsin of the native peptide gave free Leu, a tripeptide,...
9 (a) In the box below, draw the dipeptide Phe-Arg at pH 7, with the N-terminus at the left and the C-terminus on the right. 9 (b) Draw a single box around the three non-hydrogen atoms directly involved in the peptide bond. 9 (c) Label the Phi (φ) and Psi (ψ) torsion angles in your drawing. 9 (d) How many positive charges are on this dipeptide at pH 7? 9 (e) What is the total net charge at pH 7...
Which of these protein sequences is most likely to span a cell membrane? Gly-Asp-Val-Ala-Gly-Arg-Gly-Asn-Gly-Lys-Lys-Pro-Ser-Ser-Val-Arg-Ala-Leu-Ser Ile-Val-Leu-Pro-Ile-Val-Leu-Leu-Val-Phe-Leu-Cys-Leu-Gly-Val-Phe-Leu-Leu-Trp Lys-Asn-Trp-Arg-Leu-Lys-Asn-Ile-Asn-ser-Ile-Asn-Phe-Asp-Asn-Pro-Val-Tyr-Gln A. 773 B. 792 C. 811
Draw structure of this peptide at pH 7 and at pH 11. Ala-Arg-Asn-Asl-Glu-Ser-Gly Asp*
draw polypeptide for arg-His-ala at ph 6.4
6. A peptide has the sequence Cys-His-Phe-Glu-Ala-Arg a. Write the single letter sequence of the peptide b. Calculate the percentage and indicate the charge of the predominant peptide species at pH 6.5. Use the following pKa values: pKa Cys = 8.3, pKa N-terminus = 10.8, pKa His =6.0, pKa Glu = 4.3, pKa Arg = 12.5, pKa C-terminus =2.0 c. What is the charge of the peptide at pH 4.3? d. Draw the chemical structure of the predominant peptide species...