Society for Industrial Microbiology

Society for Industrial Microbiology     

Comparison of the amino acid sequences of tissue-specific parvalbumins from chicken muscle and thymus and possible evolutionary significance

Chicken leg muscle parvalbumin was digested with cyanogen bromide or trypsin or trypsin after citraconylation. Peptides isolated by reverse phase HPLC at pH 7.0 were subjected to acid hydrolysis and amino acid analysis and, in some cases, sequencing. The chicken muscle parvalbumin amino acid sequence has ca. 80% sequence identity with alpha-type parvalbumins from mammalian (rabbit, human and rat) muscle. By contrast, the chicken thymus parvalbumin ("avian thymic hormone") sequence is very similar to reptile (turtle, salamander and frog) muscle beta-type parvalbumins. We hypothesize that the evolutionary appearance of the warm-blooded reptiles was accompanied by recruitment of the beta parvalbumin isozyme for promotion of lymphocyte maturation.     

Detergent induced inhibition of eukaryotic RNA polymerase B activity and amanitin binding

We studied the effect of detergents on the binding of amanitin to RNA polymerase and on enzymatic activity. SDoS, Sarkosyl and deoxycholate were most inhibitory. Cholate and non-ionic detergents were less inhibitory. Evidence is presented that Sarkosyl inhibits chain elongation. The inhibition of amanitin binding was most influenced by the hydrophilicity of the detergent.     

Partial duplication of the long arm of chromosome 5: A case due to balanced paternal translocation and review of the literature

Summary A partial duplication of the distal segment of the long arm of chromosome 5 (q31qter) was observed in an infant with congenital malformations and dysmorphic features. The phenotypically normal father had a balanced translocation between the long arm of chromosome 5 and the short arm of chromosome 9: 46,XY,t(5;9)(q31;p24).The clinical and cytogenetic data obtained from six patients with partial duplications of two different long arm segments of chromosome 5 suggest that partial duplication of the distal long arm of chromosome 5 is associated with microcephaly, hypertelorism, epicanthus, strabismus, large upper lip, low-set, dysplastic ears, in addition to growth and psychomotor retardation. Partial duplication of the proximal part of the long arm of chromosome 5, on the other hand, is associated mainly with musculoskeletal abnormalities including muscle hypotrophy and hypotonia, scoliosis, lordosis, pectus carinatum, cubitus valgus, and genu valgum, in addition to psychomotor retardation. The dysmorphic features in this latter group include a bulging forehead, short nose, thick upper lip, low-set protruding ears and tapering, thin fingers.     

Relation of cytolytic activity of an ether-deoxy lysophosphatidylcholine analog to available membrane surface. Comparison of normal and tumor cells from mice

1-Hexadecylpropanediol-3-phosphorylcholine, an ether-deoxy analog of lysophosphatidylcholine, has been employed to study the sensitivity of various types of mouse cells with respect to changes in membrane permeability induced by lysophosphatidylcholine. Cells used included erythrocytes, thymocytes, spleen cells and macrophage, as well as 4 different tumors (2 lymphomas, 1 Ehrlich acites and 1 methylcholanthren-induced fibrosarcoma). The sensitivity to the lysophosphatide (on a per-cell basis) of the above cell types varied by a factor of 65. When lytic concentrations were related to available membrane surface, this variation was reduced to a factor of 2.5. No principal difference was observed between the sensitivity of normal versus tumor cell membranes with respect to lysophosphatidylcholine lysis. Membrane surface, available for lysophosphatidylcholine, has been estimated from binding equilibria of 14C-labelled deoxy-lysophosphatidylcholine to the cells under standardized conditions. This method is based on the finding that binding equilibria of lysophospholipids to cells are predominantly determined by the available membrane surface.     

Salicylate reduces serum insulin concentrations in the rat

Administration of sodium salicylate (50–500 mg/kg, i.p.) reduced serum insulin concentrations in nonfasted rats. This treatment also suppressed the rise in serum insulin that followed oral administration of glucose (by stomach tube) to fasted rats; this effect is only partly attributable to the blunted increase in serum glucose concentrations.     

Isolation and properties of a ferredoxin from Anabaena Flos-Aquae

Ferredoxin was isolated from the blue-green alga Anabaena flos-aquae. Its homogeneity was shown by conventional and SDS-polyacrylamide gel electrophoresis, and isoelectric focusing on polyacrylamide gel columns, the latter indicating a pI at ca pH 3·7. The absorption spectrum had, in the oxidized state, maxima at 462, 421, 327 and 276 nm, with a shoulder at 284 nm, a spectrum characteristic of plant-type ferredoxins. The 421 : 276 nm absorbance ratio was typically 0.49. The ferredoxin effectively mediated the photoreduction of NADP⁺ by barley chloroplasts depleted of native ferredoxin. The MW obtained by sedimentation-equilibrium and sedimentation velocity-diffusion coefficient studies was ca 12 000 daltons, a value somewhat higher than suggested by amino acid composition data. The ferredoxin contained 2Fe and 2S per molecule.