We have identified two basic residues that are important for the recognition of secretin and vasoactive intestinal peptide (VIP) by their respective receptors. These two peptides containing an Asp residue at position 3 interacted with an arginine residue in transmembrane helix 2 (TM2) of the receptor, and the lysine residue in extracellular loop 1 (ECL1) stabilized the active receptor conformat...

SH2 domains are protein modules which interact with specific tyrosine phosphorylated sequences in target proteins. The SH2 domain of the Src kinase binds with high affinity to a tyrosine phosphorylated peptide containing the amino acids Glu, Glu, and Ile (EEI) at the positions +1, +2, and +3 C-terminal to the phosphotyrosine, respectively. To investigate the degree of selectivity of the Src SH2...

The phosphodiesterase 5A, hydrolyzes cGMP, is expressed in the corpus cavernosum and main player behind erectile dysfunction. Inhibition of PDE5A is therefore a natural target in treatments of erectile dysfunction. Fulvic acid which is a principal constituent of shilajit (a natural substance used against erectile dysfunction) was found to be stably bound to Q pocket of catalytic site of PDE5A a...

The sequence of 27 residues at the carboxyl end of the single polypeptide chain of porcine pepsin has been found to be: -Ile-Leu-Gly-Asp-Val-Phe-Ile-Arg-Gln-Tyr-Tyr-ThrVal-Phe-Asp-Arg-Ala-Asn-Asn-Lys-Val-Gly-Leu-Ala-ProVal-Ala. The peptides from which this sequence has been derived were isolated from tryptic and chymotryptic digests of pepsin and its reduced aminoethylated and trifluoracetylate...

A method for the determination of phosphorylation sites in phosphoproteins based on column-switching high-performance liquid chromatography (HPLC) has been developed. The HPLC system consisted of a titania precolumn for the selective adsorption of phosphopeptides, an anion-exchange analytical column and a UV detector (215 nm). Rabbit muscle phosphorylase a (RPa) and porcine stomach pepsin (PSP)...

AeHuIFN a A( 30-43)-( 123-137)-NH2, Ac-Leu-Lys-Asp-Arg-His-Asp-Phe-Gly-PhePro-Gln-Glu-Glu-Phe-Phe-Gln-Arg-Ile-Thr-Leu-Tyr-Leu-Lys-Glu-Lys-Lys-Tyr-SerPro-NH2 was synthesized toward encompassing the "active site" of the interferons. The design of this 29-amino acid peptide was based on considerations of homology between the different interferons and on combining two regions of interferons, and on...

Significant progress has been made in characterizing broadly neutralizing antibodies against the HIV envelope glycoprotein Env, but an effective vaccine has proven elusive. Vaccine development would be facilitated if common features of early founder virus required for transmission could be identified. Here we employ a combination of bioinformatic and operations research methods to determine the...

A common overlapping site on the N-terminal IgV-like domain of human carcinoembryonic antigen (CEA)-related cell adhesion molecules (CEACAMs) is targeted by several important human respiratory pathogens. These include Neisseria meningitidis (Nm) and Haemophilus influenzae (Hi) that can cause disseminated or persistent localized infections. To define the precise structural features that determin...

The present study was undertaken to examine the frequencies of GSTM1 (Null/Present), GSTP1 (Ile105Val) and p53 (Arg72Pro) genotypes and their relations to breast cancer susceptibility in South Indian women. This case - control study involved 250 consecutive breast cancer cases and 500 healthy controls matched in five-year age categories in the ratio of 1:2. Genotyping was performed by PCR for G...

Olfactory discrimination of amino acids was investigated in brown bullhead catfish (Ameiurus nebulosus). Based on the magnitude of the observed food search activity of catfish conditioned to single amino acids, the tested compounds were classified as being detected by the catfish as equal to, similar to, or different from the conditioned stimulus. L-Proline (L-Pro)-conditioned brown bullhead ca...