PubMed Health⌕ Search

Biomedical subjects

G S Bailey

Publications and source records attributed to G S Bailey.

At least 127 records · Page 7Linked to original sources

The immunological similarity of rat glandular kallikreins.

The immunological properties of the submandibular kallikrein, urinary kallikrein, pancreatic kallikrein and pancreatic prekallikrein of the rat were studied by immunodiffusion, immunoelectrophoresis and radioimmunoassay. Although they behaved differently electrophoretically, all the antigens showed identical immunological behaviour. The implications of this are discussed.

Animals↗

Automated sequencing of insoluble peptides using detergent. Bacteriophage fl coat protein.

Peptides which are highly nonpolar and insoluble under moderate conditions of pH and ionic strength cannot be subjected to automated sequence analysis. We report a method for solubilization of one such peptide, bacteriophage fl coat protein, by chemical modification in the presence of sodium dodecyl sulfate. Following this treatment the 50-residue peptide was degraded stepwise in an automated sequenator using a single cleavage Quadrol program with high repetitive yield through residue 47. We also report a modified program using detergent incorporated into dimethylallylamine buffer which permitted sequencing with high repetitive yields for at least the first 18 residues of the unmodified and otherwise highly insoluble coat protein. The presence of detergent caused no observable difficulties in detection of residues by gas chromatography, thin layer chromatography, or amino acid analysis.

Amino Acid Sequence↗

Gene duplication in salmonid fishes: evidence for duplicated but catalytically equivalent A4 lactate dehydrogenases.

Skeletal muscle tissues from many species of salmonid fish are known to exhibit a set of three of five isozymes for A4-type lactate dehydrogenase (L-lactate: NAD oxidoreductase, E.C. 1.1.1.27), but the genetic basis for this isozyme system has not previously been assessed. This isozyme system was purified to homogeneity from salmon (Oncorhynchus tshawytscha) and shown to be composed of two polypeptides. Aalpha and Abeta, in binomial tetrameric combinations. Amino acid analysis revealed that Aalpha and Abeta are closely related but genetically distinct proteins, and thus are coded for the recently duplicated structural loci. Catalytic studies on the purified intact salmon isozyme system and on the isozymically pure Aalpha4 and Abeta4 homotetramers from brown trout (Salmo trutta) revealed no significant differences in catalytic properties among these enzymes, suggesting equivalent catalytic function of Aalpha and Abeta. These results, in combination with studies on polypeptide and isozyme ratios, suggest that one of the duplicated loci in salmon may be drifting toward a nonfunctional state by accumulation of mutations in regulatory DNA rather than in the structural gene itself.

Amino Acid Sequence↗

Immunological properties of nerve growth factors.

Antisera were raised against nerve growth factors isolated from mouse salivary gland and five venoms representative of the three main families of poisonous snakes. Immunochemical cross-reactivity was assessed from the ability of the antisera to inhibit the biological activities of the heterologous antigens. The high and low molecular weight forms of the salivary gland factors were found to be immunologically identical but distinct from the snake venom factors. The snake venom factors, on the other hand, were immunologically closely related to each other but not identical.

Animals↗

Purification and properties of a kininogenin from the venom of Vipera ammodytes ammodytes.

A kininogenin (EC 3.4.21.8) was purified from the venom of Vipera ammodytes ammodytes (European sand viper) by a combination of gel filtration and ion-exchange chromatography. The enzyme is approximately six times more active than bovine trypsin in its ability to release vasoactive peptides from a plasma precursor. The kininogenin is a glycoprotein containing 18-20% by weight of carbohydrate. It showed a mol. wt. of 40500 on gel filtration. Gel electrophoresis of the reduced sample in the presence of sodium dodecyl sulphate and 2-mercaptoethanol revealed the presence of two major components of mol.wt. 34300 and 31300. The heterogeneity, which was also observed on disc electrophoresis, was removed by incubation with neuraminidase. After incubation with neuraminidase the kininogenin retained full enzymic activity and possessed an isoelectric point of pH7.2. The carbohydrate content has been decreased to 10% by weight, and the single component seen on electrophoresis in the presence of sodium dodecyl sulphate and 2-mercaptoethanol corresponded to a mol.wt. of 29500.

Amino Acids↗

Purification and specificity of prolyl dipeptidase from bovine kidney.

Prolyl dipeptidase (iminodipeptidase, L-prolyl-amino acid hydrolase, EC 3.4.13.8) was purified 180-fold from bovine kidney. The enzyme which was obtained in a 10% yield was completely separated from a number of known kidney peptidases including an enzyme of very similar substrate specificity, proline aminopeptidase (L-prolyl-peptide hydrolase, EC 3.4.11.5). The specific activity of the enzyme with L-prolylglycine as substrate is 1600 units of activity per mg protein. Optimum activity of the enzyme is at pH 8.75 and the molecular weight on gel filtration was estimated to be 100 000. The isoelectric point of the enzyme is pH 4.25. Studies of substrate specificity showed that the enzyme preferentially hydrolyzes dipeptides and dipeptidyl amides with L-proline or hydroxy-L-proline at the N-terminus. Longer chain substrates with N-terminal proline were not hydrolyzed.

Animals↗

Lactate dehydrogenase isozymes of salmonid fish. Evidence for unique and rapid functional divergence of duplicated H-4 lactate dehydrogenases.

Salmonid fish, as a result of total genome duplication, have two genes, Ldh H and Ldh H', coding for polypeptides H and H', respectively, both of which have been shown in their tetrameric forms to be immunologically related to the classical H-4 lactate dehydrogenase isozyme of higher vertebrates (Bailey, G. S., and Wilson, A. C. (1968) J. Biol. Chem. 243,5843). The H-4 and H'-4 isozymes have now been highly purified from quinnat salmon, and their chemical, physical, immunological, and catalytic properties examined, and compared to the M-4 isozyme of salmon. The two proteins H-4 and H'-4 are shown to be very similar in amino acid composition, but significant differences in a few residues suggest differences in amino acid sequences. This suggestion was born out by quantitative immunological experiments in which the H-4 and H'-4 isozymes were shown to be about as different from each other as are the H-4 lactate dehydrogenases of chicken and duck. This suggests that the gene duplication event in salmon which give rise to two Ldh H genes occurred approximately 80 to 100 million years ago. The H'-4 lactate dehydrogenase which has risen from this duplication in salmon is shown to be somewhat intermediate between H-4 and M-4 in thermal stability, and in all catalytic properties examined, including substrate optima, Michaelis constants, and susceptibility to inhibition by high levels of substrate. In particular the H'-4 isozyme is almost exactly intermediate between H-4 and M-4 in its resistance to product inhibition by lactate, the catalytic parameter suggested to be of major functional importance to M-4 lactate dehydrogenase isozymes (Stambaugh, R., and Post D. (1966) J. Biol. Chem. 241,1462). Further, tissue distribution of these isozymes in salmon and trout are shown to be unusual. The M-4 isozyme salmon and trout are shown to be unusual. The M-4 isozyme occurs in very few tissues in detectable levels. It is the H-4 and H'-4 rather than H-4 and M-4, which occur in independently variable but significant levels in most tissues examined. Thus the H'-4 isozyme, despite its very close structural similarity to H-4 appears to possess functional properties which are different from either H-4 or M-4 in salmon, and some properties are midway between the two. This finding, together with the unusual tissue distribution of these isozymes, suggests that salmon with H'-4 lactate dehydrogenase is evolving to function catalytically in the absence of a balanced H-4-M-4 isozyme complement in most tissues. This balance seems to be met in most tissues by combinations of H-4 and H'-4,

Amino Acids↗