Isolation of Bacillus licheniformis mutants for stable production profiles of alkaline protease

Summary A phenotypic requirement for cysteine was introduced inBacillus licheniformis producing alkaline protease to facilitate its isolation from poor or nonproducerBacillus species. This facilitated purification of the strain in cases of cross-contamination, preparation of good inocula for commercial production and stabilization of alkaline protease harvest values, alleviating economic losses incurred through cross-contamination.     

Structural analysis of a maize gene coding for glutathione-S-transferase involved in herbicide detoxification

Summary We have used the cDNA clone encoding maize glutathione-S-transferase (GST I) to isolate a genomic DNA clone containing the complete GST I gene. Nucleotide sequence analysis of the cDNA and genomic clones has yielded a complete amino acid sequence for maize GST I and provided the exon-intron map of its gene. The mRNA homologous sequences in the maize GST I gene consist of a 107 bp 5 untranslated region, a 642 bp coding region and 340 bp of the 3 untranslated region. They are divided into three exons by two introns which interrupt the coding region. The 5 untranslated spacer contains an unusual sequence of pentamer AGAGG repeated seven times. The inbred maize line (Missouri 17) contains a single gene for GST I, whereas the hybrid line (3780A) contains two genes. Nucleotide sequence analysis of the primer extended cDNA products reveals that the 5 untranslated regions of the two genes in the hybrid 3780A are identical except for a 6 bp internal deletion (or insertion). The amino acid sequence of maize GST I shares no apparent sequence homology with the published sequences of animal GST's and represents the first published sequence of a plant GST. re]19850813 ac]19851126     

Renal neuraminidase. Characterization in normal rat kidney and measurement in experimentally induced nephrotic syndrome.

Several lines of evidence suggest that increased neuraminidase activity may be responsible for the loss of glomerular N-acetylneuraminic acid (AcNeu) observed in various glomerular diseases. However, virtually no information is available on the activity of neuraminidase in glomeruli or the potential role of this enzyme in glomerular pathophysiology. Utilizing 2'-(4-methylumbelliferyl)-alpha-D-N-acetylneuraminic acid (4MU-AcNeu) as substrate, we defined optimal assay conditions and characterized neuraminidase activity in glomeruli and, for comparison, in other renal fractions and liver. Neuraminidase activity in glomeruli, cortex and tubules was maximal at pH 4.4. The Km for 4MU-AcNeu was estimated to be 195 microM for glomeruli and 226 microM for cortex. Glomerular neuraminidase was inhibited by AcNeu (90% at 25 mM) and high concentrations of Triton X-100 (26% at 0.5%), but unaffected by CaCl2, EDTA or N-ethylmaleimide (each 1 mM). Neuraminidase activity (nmol/h per mg of protein; mean +/- S.E.M.) in normal rat kidney was: cortex, 14.47 +/- 0.76; medulla, 7.85 +/- 0.64; papilla, 2.64 +/- 0.11; tubules, 13.79 +/- 0.70; glomeruli, 5.57 +/- 0.28. In comparison, neuraminidase activity in rat liver was 2.58 +/- 0.14. Puromycin aminonucleoside (PAN)-induced nephrotic syndrome is a model of glomerular disease in which the loss of glomerular AcNeu is well documented. In two separate studies, we observed no change in the specific activity of neuraminidase in either glomeruli or cortex isolated from rats treated with PAN (15 mg/100 g, intraperitoneally) and killed at either the onset or the peak of proteinuria. Results were similar whether neuraminidase activity was expressed per mg of protein or per microgram of DNA.     

Site-related differences in the localization of the monoclonal antibody OX7 in SL2 and SL1 lymphomas

Summary The uptake of a monoclonal antibody (OX7) by murine lymphomas (SL1, SL2) growing in two sites in the mouse were compared. SL2 tumors grown in the subrenal site showed greater specific antibody uptake than did the same tumor grown in the subcutaneous site. Major differences in membrane bound antibody, in vitro antibody binding patterns, and gamma scintillation camera imaging were also observed between the two sites. These differences may be due to the greater blood flow measured in tumors growing in the subrenal capsule than those growing at the subcutaneous site. The differences observed in antibody uptake of the same tumor growing in two different sites raises questions concerning the choice of animal model systems that can be used to predict clinical utility.     

Numerical taxonomy of some non-saccharolytic and saccharolytic Bacteroides species

Various Bacteroides spp. were examined by physiological tests, presence of specific enzymes, antibiotic sensitivity, menaquinone composition and a few miscellaneous tests. The data matrix containing 58 strains and 55 unit characters was examined using Gower's similarity coefficients (SG) and included matching negative character states and multistate characters. The highly saccharolytic strains were separated from the less saccharolytic and non-fermentative strains at the 55% similarity level; while at the slightly higher level of 63% strains of Capnocytophaga (formerly Bact. ochraceus) were recovered as a compact phenon distinct from other saccharolytic species. The phenogram was divided into 6 clusters at 72% similarity level. Most of the 'Bact. fragilis group' of species clustered in one phenon while Bact. melaninogenicus ssp. melaninogenicus, Bact. bivius and a new species, Bact. denticola, formed another group. Another phenon comprised the saccharolytic non-pigmented species closely related to Bact. oralis such as Bact. buccalis and Bact. pentosaceus. The less saccharolytic strains of Bact. melaninogenicus ssp. intemedius and Bact. disiens were recovered in a distinct phenon. The low affinity (less than 55% similarity) between the two subspecies of Bact. melaninogenicus emphasised the need for reclassifying these taxa into separate species. The non-fermentative and very weakly saccharolytic strains formed good taxospecies. The separation of this cluster into three subclusters is in excellent agreement with chemotaxonomic data now available.     

THE DESMOSTEROL REDUCTASE ACTIVITY OF RAT BRAIN DURING DEVELOPMENT1

Abstract— The reduction of desmosterol by cell-free preparations from developing rat brain was established and the age-dependent alterations in reductase activity were correlated with levels of desmosterol in brain. An increase in enzymic activity followed closely the sharp increase in levels of desmosterol that was observed at about 5 days of age and that reached a maximum at 8-11 days of postnatal age. Furthermore, the abrupt decrease in the desmosterol content of brain at 13-15 days of age was associated with a decrease in enzymic activity. We suggest that the enzyme may be substrate-induced and that this attribute may be of significance with respect to the ontogenesis of myelin. Cerebral desmosterol reductase exhibited a specific requirement for NADPH and was primarily a particulate enzyme.