[D-p-Cl-Phe6,Leu17]-VIP TFA is a competitive and selective antagonist of vasoactive intestinal peptide (VIP) receptor, with the IC50 of 125.8 nM. [D-p-Cl-Phe6,Leu17]-VIP TFA has no activity on glucagon, secretin or GRF receptors[1][2][3].
2.;;Calculate the overall charge of the entire peptide according to the following table:
;
Contents
Assign value
Acidic amino acid
Asp (D), Glu (E), and the C-terminal -COOH.
-1
Basic amino acid
Arg (R), Lys (K), His (H), and the N-terminal -NH2
+1
Neutral amino acid
Gly (G), Ala (A), Leu (L), Ile (I), Val (V), Cys (C), Met (M), Thr (T), Ser (S), Phe (F), Tyr (Y), Trp (W), Pro (P), Asn (N), Gln (Q)
0
3.;;Recommended solution:
Overall charge of peptide
Details
Negative (lt;0)
1.;;Try to dissolve the peptide in water first. 2.;;If water fails, add NH4OH (lt;50 μL). 3.;;If the peptide still does not dissolve, add DMSO (50-100 μL) to solubilize the peptide.
Positive (gt;0)
1.;;Try to dissolve the peptide in water first. 2.;;If water fails, try dissolving the peptide in a 10%-30% acetic acid solution. 3.;;If the peptide still does not dissolve, try dissolving the peptide in a small amount of DMSO.
Zero (=0)
1.;;Try to dissolve the peptide in organic solvent (acetonitrile, methanol, etc.) first. 2.;;For very hydrophobic peptides, try dissolving the peptide in a small amount of DMSO, and then dilute the solution with water to the desired concentration.
参考文献
[1]. Pozo D, et, al. Characterization of VIP receptor-effector system antagonists in rat and mouse peritoneal macrophages. Eur J Pharmacol. 1997 Mar 5; 321(3): 379-86.
[3]. Messmer B, et, al. Regulation of exocrine pancreatic secretion by cerebral TRH and CGRP: role of VIP, muscarinic, and adrenergic pathways. Am J Physiol. 1993 Feb; 264(2 Pt 1): G237-42.