Comparative Biochemistry and Physiology. B, Comparative Biochemistry

1. In a number of tissues, Ca2+ signaling involves Ca(2+)-induced Ca2+ release (CICR) from ryanodine- and caffeine-sensitive intracellular Ca2+ stores. We sought evidence for such a mechanism in bovine corneal epithelial cells (BCE). 2. We have identified a microsomal fraction of BCE which possesses high-affinity [3H]-ryanodine binding sites indicating the presence of the ryanodine receptor Ca2+ channel. 3. Functional evidence for CICR is that in fura-2 loaded BCE the magnitude of Ca2+ transients induced by the addition of either the adenylate cyclase activator, forskolin, or the L-type Ca2+ channel agonist, BAY-K 8644, were both enhanced by preincubation with 5 microM ryanodine...

1. We use protein gel-electrophoresis to investigate genetic heterogeneity at 33 protein coding loci in a total of 46 blue wildebeest (C. taurinus) kept under different management regimes. 2. Average heterozygosity ranged from 2.14 to 4.3% and within-population differences accounted for 97.2% of total relative gene diversity. 3. Comparatively little divergence was found between animals sampled from populations with very diverse population sizes and management histories, with the largest genetic distance estimated between any two populations being only 0...

1. Ovine placental lactogen was modified by reaction with o-nitrophenylsulfenyl chloride. Fluorescence measurements indicated that one of the two tryptophan residues of the molecule had reacted. Besides, there was some reagent not covalently bound. 2. The reagent was covalently bound to Trp-150. No evidence of modification of Trp-90 was found. 3. Binding capacity to lactogenic as well as somatogenic receptors was diminished but not abolished upon modification, indicating that absolute molecular integrity of Trp-150 is not required for binding...

1. We dissected, homogenized and prepared ganglia and connectives from the central nervous system of medicinal leeches for SDS gel electrophoresis. The isolated proteins were transferred to nitrocellulose and incubated with affinity column-purified antibodies. 2. The immunoblots showed a strong positive reaction of a bovine carbonic anhydrase standard at a molecular weight of 29 kDa, and a distinct double-bond at the same molecular weight in the analyzed material. 3. We demonstrated with rat antibodies that carbonic anhydrase II is detectable in the leech central nervous system as the main isoenzyme...

1. Pig synovial fibroblasts in culture were studied to determine if they were an easily reproducible model system for studying the actions of cytokines and growth factors on human synovial cells. The biochemical analyses were conducted by activity assays, enzymography and Northern blot. 2. Human recombinant interleukin-1 alpha, basic fibroblast growth factor and transforming growth factor-beta 1 were studied in combinations because of their known involvement in controlling tissue remodelling. 3. The response of pig fibroblasts to these agents, in terms of the expression of matrix metalloproteinases (collagenase, gelatinase and stromelysin) and their inhibitors (TIMPs), show that they behave similarly enough to human cells for use when supplies of human primary cells are unavailable...

1. Mouse plasma creatinine measured by fuller's earth (15.1 +/- 0.5(41) microM, mean +/- SE) exceeded the same pools read by HPLC [7.5 +/- 0.2(41); P < 0.001]. 2. For mouse urine, the fuller's earth method (3.26 +/- 0.21 mM) slightly exceeded the HPLC method (2.65 +/- 0.18; P < 0.001) with good correlation (r = 0.915, P < 0.001). 3. An enzymatic method (creatinine PAP, Boehringer-Mannheim Diagnostics) for plasma creatinine (5.2 +/- 0.3 microM) was equivalent to HPLC (6.1 +/- 0.1, NS) but with poor correlation (r = 0...

1. Periplaneta lectin of the American cockroach was shown to have affinity to bacterial lipopolysaccharides (LPS) of chemotypes Rb-Re, but not to lipid A. 2. 2-Keto-3-deoxy octonate (KDO) was the most effective sugar so far tested for inhibition of the hemagglutinating activity of Periplaneta lectin. 3. Periplaneta lectin was suggested to participate in the clearance of bacteria injected into the abdominal cavity of the cockroach.

1. The AVP-like insect diuretic hormone is a biologically active antiparallel dimer present, along with its non-active monomeric form (Cys-Leu-Ile-Thr-Asn-Cys-Pro-Arg-GlyNH2), in the African locust. 2. It exhibits diuretic activity by increasing fluid excretion at the level of the Malpighian tubules. 3. To date, both monomer and dimer have been assayed using a radioimmunoassay originally prepared for mammalian AVP. 4. We have developed here an original enzyme immunoassay based on the use of antibodies to insect AVP-like raised in rabbits against synthetic monomers and dimers, using acetylcholinesterase conjugate as an enzymatic tracer...

1. The biological properties of venoms from juvenile and adult common tiger snakes (Notechis scutatus) were compared. 2. The lethality, procoagulant activity and enzymatic activities of the juvenile venom were not substantially different from those of the adult venom. 3. Electrophoretic studies, however, indicated some minor differences in the protein composition of the juvenile and adult venoms.

1. Parathyroid hormone-related peptide (PTHrP), originally isolated from human malignant tumors, is present in a variety of normal mammalian tissues, including the brain. 2. The expression and translation of the PTHrP gene within the rat hypothalamus was demonstrated in this study by the specific hybridization of a 1.8 kb mRNA product with a PTHrP cDNA probe and by the crossreactivity of rat hypothalamic extracts in a PTHrP radioimmunoassay. 3. These results suggest roles for PTHrP in neural or hypophysiotropic regulation...

1. In erythrocytes of both species, deamination and phosphorylation of dADO was completely inhibited by 5 microM 2'deoxycoformycin and 10 microM 5-ITU respectively. 2. Under physiologic conditions, provided with nanomolar concentrations of dADO there was complete deamination of dADO in human red cells. In opossum erythrocytes deamination and phosphorylation of the deoxynucleoside were nearly; additionally, 1-2% of the substrate was metabolized to AXP. 3. With ADA inhibited in intact red cells, apparent Km and Vmax for dADO were 0...

1. Polyethyleneglycol-modified bovine adenosine deaminase was administered (10-20 U/kg/week) intramuscularly to two opossums for 15 weeks and changes in red cell adenine ribo- and deoxyribonucleotides quantitated by HPLC. 2. Only a moderate decline of erythrocyte dAXP was observed at the end of the study when compared to results of enzyme replacement seen in human adenosine deaminase deficient patients. 3. Opossum red cells salvage substantial amounts of deoxyadenosine provided in physiologic (50 nM) concentration from plasma having either low or high adenosine deaminase activity...

1. Estradiol supplementation resulted in heat-stress mortality in both intact and caponized cockerels accompanied by depressed plasma corticosterone. 2. Phenotype-selection for large comb and high plasma testosterone increased heat tolerance which was attributed to an increased plasma corticosterone. 3. The results suggested that the presence of testosterone had a positive influence on the heat tolerance of broiler cockerels.

1. Human liver contains a rather high level of glycine N-methyltransferase. 2. The enzymes from human, rat, rabbit and pig livers are all tetramers and exhibit positive cooperativity toward S-adenosylmethionine and Michaelis-Menten kinetics toward glycine. The [S]0.5 values for S-adenosylmethionine and glycine of the rat enzyme are considerably lower than those of three other enzymes. 3. The subunit of rat glycine N-methyltransferase is shorter by two residues compared with the subunits of human, rabbit and pig glycine N-methyltransferases...

1. The venoms of two Mojave rattlesnakes and those of their offsprings were analyzed for Mojave toxin and hemorrhagic toxin. 2. The venom of one female, collected in Pima County, Arizona, and the venoms of her six offspring contained hemorrhagic toxin but not Mojave toxin (venom B). 3. The venom of the second female, captured in El Paso County, Texas, contained both toxins (A+B venom). Of her 10 offspring, five contained venom with both toxins, two had hemorrhagic toxin only, and three contained neither toxin...

1. The crystallin proteins of numerous species belonging to different classes of vertebrates have been studied. 2. Species-specific crystallin patterns are revealed which unequivocally characterize the different species. 3. A marked variability in the number and percentage of alpha-, beta- and gamma-crystallins were found in the various species. 4. The gamma-crystallin family, with a meagre number of common bands, has proved to be most representative of the species. The beta-crystallins, with their greater number of common bands, have been best preserved throughout vertebrate evolution...

1. Co-isolating proteins (M(r) 170,000-220,000) from sodium channel preparations made from the electric organ of the electric eel (Electrophorus electricus) were detected on Western blots using monoclonal antibodies. 2. Similar protein patterns were seen on immunoblots containing immunoprecipitated protein from eel muscle and brain tissues but not heart. 3. These co-isolating proteins could be separated from the mature TTX-sensitive channel protein (M(r) 280,000) using a lentil lectin-Sepharose column. 4. The 180 kDa proteins do not appear to be channel-related and can be detected as contaminants in electroplax sodium channel preparations using the monoclonal antibodies described here...

1. The content of atrial natriuretic peptides (ANPs) in the auricles of oysters, Crassostrea virginica, was significantly (P < 0.01) greater than in their ventricles. 2. High-performance gel permeation chromatography (HP-GPC) followed by ANF radioimmunoassay revealed two peaks in both oyster and vertebrate (rat) hearts--a major peak where the 12.6-14 kDa ANF prohormone elutes and a smaller peak where the pure human form of ANF elutes. 3. HP-GPC evaluation followed by proANF 31-67 radioimmunoassay revealed only an ANF-like prohormone while HP-GPC followed by proANF 1-30 radioimmunoassay revealed the ANF prohormone and a proANF 1-30-like peptide in oyster and rat hearts...

1. A genetically determined polymorphism of alpha-1 antitrypsin is demonstrated in dog serum by isoelectric focusing in a pH range of 3.5-5.0, followed by direct immunoblotting using a specific antiserum. 2. Alpha 1 antitrypsin focuses as two major bands at isoelectric points of 4.60 and 4.64 or 4.67 and 4.7 in presumed homozygous animals. Heterozygotes show both sets of bands. 3. The results of seven crosses with 33 offspring are best explained by two codominant alleles, PiM and PiS at a single locus designated as Pi for proteinase inhibitor...

1. The genetic code was thought to be identical ("universal") in all biological systems until 1981, when it was discovered that the coding system in mammalian mitochondria differed from the universal code in the use of codons AUA, UGA, AGA and AGG. 2. Many other differences have since been discovered, some in mitochondria of various phyla, others in bacteria, ciliated protozoa, algae and yeasts. 3. The original thesis that the code was universal and "frozen" depended on the precept that any mutational change in the code would be lethal, because it would produce widespread alterations in the amino acid sequences of proteins...