Conservation of DNA sequences for plasmid-mediated citrate utilization within the enterobacteria.

Southern blot DNA-DNA hybridization experiments with a cloned Cit+ DNA fragment as a probe showed that the plasmid-mediated Cit+ determinants from four Cit plasmids (R726, pOH3001, pOH3035, and pOH30221) were all homologous. Sequences homologous to the plasmid-borne Cit+ gene were also found in total bacterial DNA isolated from Salmonella paratyphi B, Salmonella enteritidis, Salmonella typhimurium LT-2, Citrobacter freundii, ATCC 8090, Citrobacter amalonaticus ATCC 25405, Klebsiella pneumoniae I and IID 977, and Enterobacter aerogenes ATCC 13048. The DNA digest from C. amalonaticus ATCC 25405 contained a 1.4-kilobase BamHI-HincII DNA fragment that was strongly homologous with and identical in size to the plasmid Cit+ probe.     

Solid-state ethanol fermentation by means of inert gas circulation

A new method for solid-state ethanol fermentation (the SSEF system) was experimented on for the ethanol production from solid starchy materials, where a packedbed-type fermentor was used. Both cultivation of Aspergillus saitoi and enrichment of a saccharifying enzyme were effective for hydrolysis of the starch. Ethanol production was set in by a form of parallel fermentation using a respiration-deficient mutant of Saccharomyces cerevisiae. Produced ethanol was simultaneously stripped by circulating inert gas and separated in a condenser. Average ethanol concentration in the condensate was over 200 g/L, and over 90% of produced ethanol was recovered from the packed bed during 15 or 16 days of stripping. The fermentation efficiency was about 80%, which was evaluated much higher than those of conventional solid-state fermentations. The residue had lesser volume and a higher solids content compared with the distillery wastewaters of conventional liquid-state fermentations. This means an advantage for the treatment and the effective conversion of the residue into fetilizers or animal feeds.     

An outbreak of staphylococcal dermatitis in laboratory mice

An epizootic of dermatitis with erosion, ulcer and crust broke out in an experimental colony of JCL-ICR mouse over a period from December 1975 to June 1976. The disease was detected in 592 of a total of 1831 mice of 3-24 months old, especially in males of 7-24 months old (517/821). At the beginning of December 1975, only a few males of 12 months old were found to have the lesion on the back skin, and thereafter the dermatitis prevailed gradually among the mice. Histopathologic examinations showed the loss of the epidermis, necrosis and/or collapse of the corium, accumulation of serous exudate with neutrophilic cell infiltration and a few cocci scattered on the surface. In chronic cases, fibrous granulation tissues with neutrophilic cell infiltration were formed in the corium. Staphylococcus aureus was isolated in pure culture from the skin lesions in all of the mice examined. Skin disease similar to that of the field case was reproduced in mice inoculated subcutaneously with 10(7) viable organisms of the fresh isolate. By giving chlortetracycline in drinking water for 7 days, treatment of the affected mice was efficacious in mild cases, but not in severe cases.     

Biological properties, phage typing and antimicrobial susceptibility of Staphylococcus aureus isolated from dermatitis in laboratory mice

The characteristics of 167 isolates of S. aureus from 106 mice suffering dermatitis were examined. All 167 isolates coagulated both rabbit and human plasmas and 161 of them also coagulated bovine plasma. All the isolates produced heat-stable and heat-labile DNase, phosphatase and yellow pigment, reduced nitrate, hydrolysed egg yolk, Tween 80, and hippurate, and grew on crystal violet agar in colonies of the negative type C and on medium with 10% NaCl. The majority of them produced fibrinolysin, protease and acetoin. Fifty-three percent were gelatinase positive. In hemolysis tests, 25, 57 and 45 isolates showed alpha-, beta-, alpha beta-hemolysis, respectively. Forty isolates did not produce hemolysins in the rabbit and sheep blood agar. All of 75 isolates tested produced acid from fructose, galactose, glucose, glycerol and mannose, but did not from arabinose, dextrin, inulin, raffinose, salicin, sorbitol and xylose. Most of these isolates produced acid from lactose, mannitol, sucrose and trehalose. All of the 75 isolates were highly sensitive to penicillin, methylphenylisoxazolyl penicillin, erythromycin, spiramycin, lincomycin, chloramphenicol, tetracycline, kanamycin, gentamicin and cephaloridine, but were resistant to sulfisoxazole. With phages of human set, all 167 isolates were typable at 100 X RTD. All but one of the typable isolates belonged to mixed lytic groups. These were I + III (35 isolates), I + M (1), I + III + M (124) and I + II + III + M (6), with long phage patterns. When the 167 isolates were biotyped as described by Hájek and Marsálek [7, 8], 5 belonged to biotype A, 1 to biotype B and 60 to biotype C.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of ethanol and phenobarbital administration on the metabolism and toxicity of benzene

Effects of ethanol- and phenobarbital(PB)-treatment on the metabolism of benzene in vitro and in vivo, and on the benzene-induced hemotoxicity, were investigated. Ethanol consumption markedly enhanced in vitro metabolism of both benzene and phenol in rat liver, whereas PB-treatment, which enhanced the metabolism of phenol to some degree (about one-third of ethanol-induced enhancement), did not affect the metabolism of benzene. In a single exposure experiment with rats, ethanol increased benzene metabolism in vivo as evidenced by accelerated disappearance of benzene from the blood as well as by elevated urinary excretion of phenol, whereas PB produced little or no significant influence on the metabolism. In a 3-week exposure experiment, ethanol administration accelerated benzene disappearance from the blood in agreement with the single exposure experiment, but it tended to decrease urinary phenol excretion with repetition of exposure, probably due to concomitant stimulation of subsequent phenol metabolism by ethanol. Again, PB-treatment produced only a negligible effect on the metabolism of benzene. Ethanol consumption aggravated benzene-induced hemopoietic disorder as evidenced by a marked decrease in the peripheral white blood cell number. PB produced a protective effect on the toxicity. It is concluded that ethanol potentiates benzene toxicity by accelerating (1) hydroxylation of benzene, a rate-limiting step of benzene metabolism and (2) transformation of phenol into highly toxic metabolites.     

Characterization of nontransformed and transformed androgen receptor from rat submandibular gland

Rat submandibular gland cytosol contained androgen receptor which had a single class of specific binding and an apparent dissociation constant of (1.1-1.2) X 10(-9) M. The process of transformation was investigated by a slightly modified minicolumn method in which the transformed receptor complexes were separated from the nontransformed receptor and meroreceptor. 10 mM ATP or pyrophosphate at 0 degrees C induced transformation of androgen receptor as did heat or salt treatment. 20 mM of sodium molybdate completely inhibited transformation that resulted from ATP, heat or salt treatment. The nontransformed androgen receptor complexes sedimented at 8 S and eluted at 250-260 mM KCl from DEAE-Sephacel, and its molecular weight was found to be 220 000 on Sephacryl S300 gel chromatography. On the other hand, the transformed androgen receptor complexes sedimented at 4.1-4.3 S (ATP or KCl treatment) or 3.5-3.8 S (heat treatment) and eluted at 60-80 mM KCl from DEAE-Sephacel. The molecular weight of the transformed androgen receptor complexes was 80 000-85 000 (ATP or KCl treatment) or 70 000-80 000 (heat treatment). These results suggest that the transformation of androgen-receptor complexes from rat submandibular gland was induced by the subunit dissociation and that salt bridges may be involved in the subunit interaction.     

Identification of heterogeneous and microheterogeneous subunits of glutathione S-transferase in rat liver cytosol

Subunits of multiple molecular forms of dimeric glutathione S-transferase in rat liver cytosol were analyzed by two-dimensional gel electrophoresis (isoelectric focusing/sodium dodecyl sulfate-electrophoresis) followed by staining with Coomassie blue dye. The five subunits, Ya, Yb, Yb', Yc, and Yp (Mr's 26,500, 27,500, 27,500, 28,500, and 26,000, respectively) of seven molecular forms, A2, AC, C2, B2, BL, L2, and GST-P, were identified by comparison of molecular weights and pI values with those of purified molecular forms and by immunoadsorption of the molecular forms in the cytosol as well as those synthesized in vitro using antibodies against the seven forms. Yp is the subunit of placental glutathione S-transferase, GST-P (YpYp), which is markedly increased in carcinogen-treated rat livers [A. Kitahara et al. (1984) Cancer Res. 44, 2698-2703; K. Satoh et al. (1985) Proc. Natl. Acad. Sci. USA 82, 3964-3968]. Microheterogeneity was detectable within Yb, Yb', and Yp subunits, the different forms, termed Yb1, Yb2, Yb'1, Yb'2, and Yp1, Yp2, being similar in size but differing by approx. 0.3 pI unit within each subunit. These microheterogeneous forms were also detectable in the polypeptides translated in vitro in a rabbit reticulocyte lysate translation system from liver poly(A)-containing RNAs, suggesting that they are translatable from distinct mRNAs.     

Differential effects of recombinant human interferon-gamma and interleukin 2 on natural killer cell activity of peripheral blood in early human development

Ontogenic development and the lymphokine responsiveness of human NK cell activity against K562 target cells in peripheral blood lymphocytes were evaluated in fetuses, premature infants, and term neonates by using a 4-hr 51Cr-release assay. Basal NK activity and NK boosting by lymphokines were comparatively assayed after an 18-hr incubation with medium alone, recombinant human IFN-gamma (1000 U/ml), and recombinant human IL 2 (25 U/ml), respectively. Lymphocytes from 20-wk-old fetuses lacked NK cell activity even after the pretreatment with IFN-gamma. Low, but significant levels of NK activity and NK boosting by IFN-gamma were observed in premature infants after 27 wk of gestation, with a progressive intrauterine maturation of these activities. Both basal NK activity and NK boosting by IFN-gamma in term neonates were still lower than those of adult controls. The grade of NK boosting by IFN-gamma appeared to depend on the development of basal NK activity. Contrary to IFN-gamma, IL 2 could induce marked NK activity even in 20-wk-old fetuses who lacked both basal and IFN-gamma inducible NK activities. NK boosting by IL 2 was much more efficient than that by IFN-gamma at any period of human life. The facts that IL 2-induced NK boosting could occur without any appreciable production of IFN-gamma in neonatal lymphocytes, and that ample neutralizing doses of anti-IFN-gamma antibody hardly suppressed IL 2-mediated NK boosting even in adult lymphocytes, indicated that the effect of IL 2 on NK boosting might be independent of IFN-gamma production. On the basis of the ontogenic differences in the development of the lymphokine responsiveness of NK cell activity and on the different NK boosting mechanisms of these lymphokines it was suggested that so-called human "pre-NK cells" might be divided into IFN-gamma sensitive and IL 2-sensitive cells. Whether these cell populations belong to different cell lineages or different maturation stages of the same cell line, however, remains unsettled.     

Central alpha-activation by clonidine reduces plasma level of beta-endorphin in patients with essential hypertension

Whether peripheral beta-endorphin contributes to the antihypertensive action of clonidine was examined by measuring plasma levels of beta-endorphin-like immunoreactivity (beta EpLI) after acute administration of clonidine in patients with essential hypertension. Administration of clonidine (0.225 mg) in one dose significantly lowered blood pressure, decreased heart rate and reduced the plasma level of beta EpLI and ACTH, while the placebo had no effect on blood pressure, heart rate or plasma level of beta EpLI suggesting that peripheral beta-endorphin does not play a major role in the antihypertensive action of acute clonidine administration.     

Nitroarenes in Suimon River sediment

Mutagenic activity was observed in sediments of the Suimon River bed with and without S9 mix. The direct-acting mutagens in the sediment were investigated. The sediment was extracted with methanol and fractionated on a Silica gel column. The benzene fraction from the Silica gel column exhibited mutagenic activity without S9 mix in strain TA98, while it failed to show mutagenic activity in nitroreductase-deficient strain TA98NR. This observation led to the suspicion that nitro compounds were the direct-acting mutagens of these samples. The benzene fraction was treated by heptafluorobutyric anhydride (HFBA) and investigated with gas chromatography equipped with an electron capture detector (GC-ECD). 2-Nitrofluorene, 4,4'-dinitrobiphenyl, 2,7-dinitrofluorene and 1-nitropyrene were detected and measured quantitatively. The mutagenic activity of a mixture of these compounds was compared with that of the original fraction and the direct-acting mutagenicity of Suimon River sediment can be explained by these nitroarenes, especially 1-nitropyrene.