Polymerization of 10-hydroxydecanoic acid in benzene with polyethylene glycol-modified lipase

Summary A hydrophobic substrate, 10-hydroxydecanoic acid having two functional groups (–OH and –COOH) in the molecule, was polymerized by ester bond formation with the polyethylene glycol-modified lipase in a transparent benzene solution. The polymer of 10-hydroxydecanoic acid was linearly elongated under a quite mild condition.     

Characterization of a Mr = 56,000 polypeptide associated with 10S DNA polymerase alpha purified from calf thymus using monoclonal antibody.

Existence of a Mr = 56,000 polypeptide associated with 10S DNA polymerase alpha was shown by production of a monoclonal anti-calf thymus 10S DNA polymerase alpha antibody secreted from a hybridoma line named 3H1. The antibody bound three polypeptides with Mr = 180,000, 56,000 and 32,000 in hydroxylapatite fraction of 10S DNA polymerase alpha by immunoblot. The antibody co-precipitated the polypeptides with the large polypeptide (Mr = 150,000-140,000) of 10S DNA polymerase alpha with the aid of second antibody. Among three polypeptides, the Mr = 56,000 polypeptide was co-purified with DNA polymerase alpha through DNA-cellulose chromatography and repeated sucrose rate-zonal centrifugations. The Mr = 56,000 polypeptide was still associated with 10S DNA polymerase alpha after second sucrose rate-zonal centrifugation, but the amount of it was reduced. The polypeptide was banded at pH 7.2-8.0 and displayed microheterogeneity in respect of isoelectric point by isoelectrofocusing with 7 M urea, and showed weak DNA-binding property after blotting onto a nitrocellulose. The antibody against the polypeptide precipitated DNA polymerase alpha from human, rat, and mouse, and Mr = 56,000 and 32,000 polypeptides were detected in these DNA polymerase alpha fractions by immunoblot. These results suggest that the polypeptide with Mr = 56,000 may take part in the DNA polymerase reaction.     

Characterization of pathogenic constituents of Cryptococcus neoformans strains

We examined seven strains, comprising five serotypes, of Cryptococcus neoformans to determine what constituents of the organisms are responsible for pathogenicity and virulence in BALB/c mice. C. neoformans strains were divided into three virulence classes by survival rates after intravenous inoculation of 1 X 10(5) or 1 X 10(7) viable cells, and virulence was found not to be correlated with serotype or capsular size. C. neoformans cells resisted phagocytosis in different degrees in the presence of normal serum. Sensitivity of the C. neoformans strains to singlet oxygen ranged from resistance to susceptibility. Histological examination revealed that a weakly encapsulated virulent strain induced inflammatory responses with granuloma formation in the liver, lung, and kidney in addition to formation of cystic foci in the brain. In contrast, although the heavily encapsulated virulent strain produced granulomatous lesions in the liver, this strain preferably produced mucinous cystic foci in the lung, kidney, and brain. Correlation between virulence, and biological, histopathological and physiological evidence suggests that C. neoformans strains are endowed with the implicated multiple pathogenic constituents in various degrees and proportions. The following are suggested as the most important pathogenic constituents: a polysaccharide capsule responsible for resistance to phagocytosis and formation of cystic foci; a cell surface structure for responsible for resistance to intra- or extracellular killing and induction of the granulomatous lesion; a growth rate suitable for interacting with phagocytic elimination.     

Spider toxin (JSTX) on the glutamate synapse

A new neurotoxin (JSTX) was separated from spider (Nephila clavata, Joro spider) venom. JSTX irreversibly suppressed the excitatory postsynaptic potential (EPSP) and the glutamate potential in the lobster neuromuscular junction with high degree of specificity. The threshold concentration for suppressing EPSPs corresponds to a small fraction of the toxin in a venom gland, roughly estimated as low as 10(-10) M/l. 10(-10) M/l. In the giant synapse of squid stellate ganglion JSTX suppressed EPSPs without affecting the antidromic response. Glutamate-induced membrane depolarization was blocked by JSTX. In mammalian brain slice preparation, JSTX suppressed the orthodromic spike response but failed to affect on the antidromic spike in the hippocampal pyramidal neuron of CA1 and CA3 region. The above results strongly support the view that the squid giant synapse and synapses in the hippocampal pyramidal neuron are mediated by glutamate.     

The standardization of the candidate national standard anti-D blood-typing serum with the Groupamatic MG50 system

The utility of the Groupamatic MG50 system for quantitative expression of agglutination in terms of continuous response was studied. By use of the characteristics of the design of this system, in which the change in voltage reflects the degree of agglutination, a linear regression relationship between the log ratio of light flux obtained by transformation of the voltage and the log dilution factor of the serum was demonstrated. The availability of the parallel line assay method to the standardization of the blood grouping antisera was also described.     

Proximity of reactive lysyl residue to the antigenic site in rabbit skeletal myosin against the monoclonal antibody (MF-18) generated to chicken skeletal myosin

MF-18, one of the monoclonal antibodies generated to chicken myosin, cross-reacted with rabbit skeletal myosin subfragment-1 (S1). Utilizing an improved procedure of immuno-blotting, a decrease in reactivity of MF-18 to S1 by trinitrophenylation was observed. This indicates that the reactive lysyl residue is very close to the hapten site. This is consistent with the evidence that the hapten site resides in the 26,000 dalton tryptic fragment of S1. Use of such antibodies as labels may open the way to determining the location of specific hapten sites in the three-dimensional image of actin-S1 complex reconstructed from the electron micrographs.     

Antigen-specific murine T-cell lymphomas. II. H-2 restriction of primary and secondary responses

A stable clone of C57BL/6 (H-2b) radiation leukemia virus transformed ovalbumin (OVA)-specific murine T-cell lymphoma cells was able to mediate carrier-specific helper activity. The ability of these lymphoma cells to express helper activity for both primary and secondary hapten-specific B-cell responses was analyzed in nonirradiated normal or hapten-primed recipients. The lymphoma cells augmented anti-hapten responses in a carrier-specific manner; no bystander effects were noted. Helper activity was primarily noted in the IgG responses. The genetic restrictions affecting the expression of lymphoma-mediated helper activity were also analyzed. The pattern of restriction indicated that genes in the H-2 complex controlled the expression of helper activity; disparities at the Igh complex failed to influence helper activity. The cellular site of the H-2 restriction was between the antigen-presenting cells and the T-cell lymphoma not between the T and B cells. Precise intra-H-2 mapping of the gene(s) which control expression of lymphoma-mediated helper activity was attempted. Although most of the data were consistent with localization of the gene(s) to the I-A region, anomolous responses were noted in one strain.     

Differential expression and distribution of chicken skeletal- and smooth-muscle-type alpha-actinins during myogenesis in culture

Antibodies to chicken fast skeletal muscle (pectoralis) alpha-actinin and to smooth muscle (gizzard) alpha-actinin were absorbed with opposite antigens by affinity chromatography, and four antibody fractions were thus obtained: common antibodies reactive with both pectoralis and gizzard alpha-actinins ([C]anti-P alpha-An and [C]anti-G alpha-An), antibody specifically reactive with pectoralis alpha-actinin ([S]anti-P alpha-An), and antibody specifically reactive with gizzard alpha-actinin ([S]anti-G alpha-An). In indirect immunofluorescence microscopy, (C)anti-P alpha-An, (S)anti-P alpha-An, and (C)anti-G alpha- An stained Z bands of skeletal muscle myofibrils, whereas (S)anti-G alpha-An did not. Although (S)anti-G alpha-An and two common antibodies stained smooth muscle cells, (S)anti-P alpha-An did not. We used (S)anti-P alpha-An and (S)anti-G alpha-An for immunofluorescence microscopy to investigate the expression and distribution of skeletal- and smooth-muscle-type alpha-actinins during myogenesis of cultured skeletal muscle cells. Skeletal-muscle-type alpha-actinin was found to be absent from myogenic cells before fusion but present in them after fusion, restricted to Z bodies or Z bands. Smooth-muscle-type alpha- actinin was present diffusely in the cytoplasm and on membrane- associated structures of mononucleated and fused myoblasts, and then confined to membrane-associated structures of myotubes. Immunoblotting and peptide mapping by limited proteolysis support the above results that skeletal-muscle-type alpha-actinin appears at the onset of fusion and that smooth-muscle-type alpha-actinin persists throughout the myogenesis. These results indicate (a) that the timing of expression of skeletal-muscle-type alpha-actinin is under regulation coordination with other major skeletal muscle proteins; (b) that, with respect to expression and distribution, skeletal-muscle-type alpha-actinin is closely related to alpha-actin, whereas smooth-muscle-type alpha- actinin is to gamma- and beta-actins; and (c) that skeletal- and smooth- muscle-type alpha-actinins have complementary distribution and do not co-exist in situ.