Phenotypic variations in re-lysogenization ofBacillus licheniformis with temperate phage

A bacitracin-producing strainBacillus licheniformis ATCC 10716 harbors two types of inducible phages (LP52 and DLP 10716). 156 strains re-lysogenized with phage LP52 were independently isolated from a cured strain UM12 ofB. licheniformis. Those strains were divided into 12 groups based on colony morphology and pigment production. Some of the re-lysogenized strains grew faster than UM12 and others produced more bacitracin than the cured strain. For example, the production of bacitracin by one of the relysogenized strains, L89, was enhanced by about 70% in comparison with UM12. The phenotypic variations observed with re-lysogenized strains might be due to the re-insertion of the phage genome at different sites of the chromosome in addition to the pleiotropic effect assumed.Abbreviations ATCC American Type Culture Collection - DNA Deoxyribonucleic acid - MC Mitomycin C - OD Optical density - PFU Plaque forming unit - rpm Revolutions per minute - UOD Unit of optical density - UV Ultraviolet Definition Specific growth rate (h^-1) - t time (h) - X cell concentration (g/l)     

Induction of Haploid Callus from Isolated Microspores of Peony in vitro

The in vitro culture of isolated microspores of two cultivarsof Paeonia, P. lactiflora cv. "Kumoinotsuru" (2n=10) and cv."Toyonoakari" (2n = 10), was attempted. With both cultivars,some cultured microspores (3–6%) began to divide afterfive to seven days of culture. Those of "Kumoinotsuru" grewinto calli, whereas the others degenerated. Cytological examinationof the callus developed from a microspore revealed haploids,diploids or a mixture of both. No direct embryo formation frommicrospores was observed in this experiment. (Received December 1, 1980; Accepted January 16, 1981)     

Effect of glucose on protein phosphorylation in rat pancreatic islets

Isolated rat pancreatic islets, incubated in the presence of extracellular ³²Pi to steady state ³²P incorporation into cellular phosphopeptides, were exposed to glucose for 10 min. Glucose (16.7 mM) significantly stimulated the phosphorylation of six phosphoproteins with molecular weights of 15,000, 35,000, 49,000, 64,000, 93,000 and 138,000. Mannoheptulose (16.7 mM) markedly inhibited glucose-stimulated phosphorylation of these six phosphoproteins. This protein phosphorylation might be important in mediating glucose-stimulated insulin release.     

Immobilized mitochondrial electron transport particle for NADH determination

Nonphosphorylating electron transport particles (ETP) prepared from beef heart mitochondrion were immobilized in agar gel. The immobilized ETP showed an oxidase activity to both NADH and succinate. The immobilized ETP was reusable. An electrochemical device for the determination of either NADH or succinate was assembled consisting of the membrane-bound ETP and an oxygen probe. The response to succinate was specifically inhibited by the addition of malonate.     

Phosphate permeability in cells ofChlorella ellipsoidea

Summary Active transport of orthophosphate byChlorella ellipsoidea was observed at 25 °C under fluorescent light, about 3 klux. Influx and efflux of phosphate, and extra- and intracellular phosphate concentrations were measured in order to assess phosphate permeability in the cells. The permeability ranged from 10^–3 to 10^–4 mlQ/mg cell min (or 10^–7 to 10^–8cm/sec).     

In vivo inhibition of cholesterol uptake in rabbit aortas by 7-ketocholesterol.

The iv injection of 7-ketocholesterol into rabbits, made soluble by combining with bile salts, inhibited cholesterol uptake by the aorta. However, the inhibition was not as marked or as uniform as previously demonstrated in in vitro experiments. This difference may have been the result of lower plasma concentrations of 7-ketocholesterol in the injected animals. Gastric feeding of 7-ketocholesterol failed to inhibit aortic cholesterol uptake, probably because of inadequate plasma concentrations of the inhibitory steroid. The results suggest that the mechanism of 7-ketocholesterol on aortic cholesterol uptake is through competitive inhibition.