-transparent.png){kind=logo}
Structure-activity studies of the lysine residue in the highly active cyclic hexapeptide somatostatin analog cyclo(Pro-Phe-D-Trp-Lys-Thr-Phe) confirm the importance of the lysine amino group for biological activity through the loss of activity seen on replacement of lysine by ornithine, arginine, histidine and p-amino phenylalanine. Three analogs containing thialysine, gamma- and delta-fluorolysine were equipotent to the parent as inhibitors of insulin, glucagon, and growth hormone release. The pKa's of the amino groups in these equiactive peptides ranged from 8.23-9.4. The lack of a correlation between the basicity of the amino groups and the biological activities suggests that deprotonation is not required for biological activity.
R F Nutt, and
D F Veber, and
P E Curley, and
R Saperstein, and
R Hirschmann
January 2003,
Journal of endocrinological investigation,
R F Nutt, and
D F Veber, and
P E Curley, and
R Saperstein, and
R Hirschmann
January 2004,
Pituitary,
R F Nutt, and
D F Veber, and
P E Curley, and
R Saperstein, and
R Hirschmann
July 1984,
Regulatory peptides,
R F Nutt, and
D F Veber, and
P E Curley, and
R Saperstein, and
R Hirschmann
August 1996,
Nuclear medicine and biology,
R F Nutt, and
D F Veber, and
P E Curley, and
R Saperstein, and
R Hirschmann
October 2006,
Polskie Archiwum Medycyny Wewnetrznej,
R F Nutt, and
D F Veber, and
P E Curley, and
R Saperstein, and
R Hirschmann
August 2001,
The journal of peptide research : official journal of the American Peptide Society,
R F Nutt, and
D F Veber, and
P E Curley, and
R Saperstein, and
R Hirschmann
January 2003,
Journal of endocrinological investigation,
R F Nutt, and
D F Veber, and
P E Curley, and
R Saperstein, and
R Hirschmann
January 2010,
Tumori,
R F Nutt, and
D F Veber, and
P E Curley, and
R Saperstein, and
R Hirschmann
September 2001,
Minerva endocrinologica,
R F Nutt, and
D F Veber, and
P E Curley, and
R Saperstein, and
R Hirschmann
January 2020,
Current protein & peptide science,
