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51.
Changes in the isoprenoid quinone composition ofMicrococcus varians IAM 12146 in response to growth in different media were investigated. When the bacterium was growth in an ordinary complex medium, it produced menaquinones as the sole quinones, with a dihydrogenated menaquinone with seven isoprene units as the major component, at all growth stages. On the other hand, cells grown in a chemically defined medium containing glutamate and pyruvate as carbon sources produced both menaquinones and demethylmenaquinones. The major demethylmenaquinone homologs produced were the unsaturated and dihydrogenated types with seven isoprene units. The demethylmenaquinone/menaquinone ratio in cells varied during a batch growth in the chemically defined medium. The highest ratio was found in cells at the mid-exponential phase of growth. 相似文献
52.
On the hoplonemertean Sagaminemertes nagaiensis (Iwata, 1957), with consideration of its systematics 总被引:1,自引:1,他引:0
Fumio Iwata 《Hydrobiologia》1988,156(1):115-124
Summary The polystiliferous hoplonemertean Sagaminemertes nagaiensis (Iwata, 1957) has been redescribed.A distinct pre-cerebral region is wanting. The rhynchocoel opens directly at the tip of the head, whilst the mouth opens seperately below the ventral commissure of the brain which is situated at the anterior end of the head. The dorsal ganglia are well developed and extend posteriorly far behind the ventral ganglia. The cerebral sense organs are situated behind the brain and possess posterior ciliated canals. Cephalic glands are poorly represented, but ocelli are well developed. The sickle-shaped basis of the proboscis bears about 20 central stylets. The caecal appendages of the rhynchocoel are arranged pseudometamerically throughout the body. The foregut is straight, consisting of mouth, oesophagus, stomach and pylorus. Intestinal caeca and lateral diverticula are present. The cephalic lacunae have no anterior anastomosis. A cerebral lacuna is present, there is a rhynchocoel vessel, but transverse vessels are absent. The protonephridia extend throughout the foregut region. Mature spermatogonia are well developed.A systematic discussion of Sagaminemertes nagaiensis suggests that it is taxonomically close to Siboganemertes weberi in the archireptantic family Siboganemertidae. 相似文献
53.
The effect of phospholipase C on two isozymes (alpha (+) and alpha forms) of rat brain (Na+ + K+)-ATPase and the temperature-dependence of their activities were investigated. Phospholipase C from Clostridium welchii inhibited the activities of the enzymes treated with and without pyrithiamin or N-ethylmaleimide, a preferential inhibitor of the alpha (+) form, but the extent of the inhibition was higher in the control enzyme than in the treated enzymes. The treatment of the (Na+ + K+)-ATPase with phospholipase C altered a ratio between high- and low-affinity components for ouabain inhibition. It also caused the similar change in a ratio between the alpha (+) and alpha forms of Na+-stimulated phosphorylation from [gamma-32P]ATP. These findings indicate that the alpha (+) form of rat brain (Na+ + K+)-ATPase is more sensitive to phospholipase C than the alpha form. Analysis of Arrhenius plots of the activities of the control and pyrithiamin-treated enzymes showed that there was a difference between the two enzymes in a break point. We suggest that two isozymes of rat brain (Na+ + K+)-ATPase differ in the interaction with phospholipids or in the lipid-environment. 相似文献
54.
Histopathological examinations on nephlocalcinosis of the Fischer 344 (F344) rats were carried out. As the results of comparison on its appearance among F344, Wistar and SD strains of rats, F344 female rats showed the most severe nephrocalcinosis. Nephrocalcinosis developed between 4 weeks and 8 weeks and was likely to keep its appearance through 108 weeks of the survival period of the rats. Histologically, mineral deposit was always observed at cortico-medullary junction. It seemed to locate at the outer portion of the basement membrane of the tubular epithelium, adjacent to the capillary wall in the connective tissue. Four weeks after ovariectomy at 4 weeks of age, the rats showed a decrease in degree of nephrocalcinosis. In contrary, the rats treated with estorone following ovariectomy revealed an increase in degree of nephrocalcinosis. It was suggested that the oestrogen-type sex hormone appeared to give a role in nephlocalcinosis. 相似文献
55.
Tetracycline-resistant (Tetr) erythromycin-resistant (Eryr) fusants of Lactobacillus fermentum 604 carrying a 10-megadalton Tetr plasmid and L. fermentum 605 carrying a 38-megadalton Eryr plasmid were obtained by means of polyethylene glycol-induced protoplast fusion. 相似文献
56.
Isolation and Identification of α-(γ-Aminobutyryl)-Hypusine 总被引:2,自引:2,他引:0
A new dipeptide, alpha-(gamma-aminobutyryl)-hypusine, was identified in bovine brain. This compound was isolated from trichloroacetic acid-soluble fraction of bovine brain with five steps of ion-exchange chromatography. Its structure was postulated by routine chemical analyses and determined by synthesis. The amount of the compound isolated from 1.2 kg of bovine brain was 870 nmol. 相似文献
57.
Establishment of a Sensitized Immunoblotting Method for Measuring Plant Tubulin Content 总被引:1,自引:0,他引:1
A sensitized immunoblotting method was established for measuringsmall amounts of plant tubulin. The method involves electrophoretictransfer of protein including tubulin from SDS-polyacrylamidegels onto nitrocellulose paper, successive incubation of thenitrocellulose paper with a mouse monoclonal antibody to - orß-tubulin of chicken brain, an antibody to mouse IgGas the second antibody and the radioactive iodinated proteinA, and determination of the radioactivities of the bands onthe nitrocellulose paper thus probed. The radioactivities werelinearly proportional to the amounts of - or ß-tubulinfrom dark-grown Vigna mungo seedlings within a range of 4 to56 ng or of 4 to 32 ng, respectively. This method was used to estimate the tubulin contents of severalplant species using Vigna tubulin as a standard. -Tubulin contentsthus estimated were 25, 9, 19 and 11 µg-equivalents ofVigna tubulin per mg protein for Vigna seedlings, Daucus suspensioncells, Catharanthus suspension cells and Mougeolia cells, respectively.ß-Tubulin contents of Vigna, Daucus, Catharanthusand Mougeotia cells were 29, 10, 13 and 5 µg-equivalentsof Vigna tubulin per mg protein, respectively. (Received August 6, 1985; Accepted December 5, 1985) 相似文献
58.
Fujioka Shozo; Sakurai Akira; Yamaguchi Isomaro; Murofushi Noboru; Takahashi Nobutaka; Kaihara Sumiko; Takimoto Atsushi; Cleland Charles F. 《Plant & cell physiology》1986,27(7):1297-1307
The occurrence and endogenous level of various plant hormoneswere measured for the short-day plants Lemna paucicostata 151and 381 and the long-day plant Lemna gibba G3 to determine whetherany of them are involved in the photoperiodic control of flowering.ABA, IAA, GA1, GA29, GA34, GA53, trans- and cis-zeatin, trans-and cis-ribosyl zeatin, N6-(2-isopentenyl) adenine and N6-(2-isopentenyl)adenosine were definitely detected in each species, while GA4was only detected in L. gibba G3 and GA20 was only detectedin L. paucicostata 151. The endogenous levels of ABA and IAAwere in the range of 17 ng/g fr wt and were not significantlydifferent in vegetative and flowering plants. The endogenousgibberellin levels were generally higher in Lemna grown underlong-day rather than short-day conditions. The endogenous cytokininlevels were almost the same in both flowering and vegetativeplants of L. paucicostata 151 and 381. In L. gibba G3, however,the level of cis-ribosyl zeatin, N6-(2-isopentenyl) adenineand N6-(2-sopentenyl) adenosine were higher in vegetative thanin flowering plants. These results indicate that there is not necessarily a directrelation between endogenous plant hormone levels and flowering,and that the chemical basis for the photoperiodic control offlowering cannot be explained solely by changes in hormone levels.The possibility remains, however, that one or more of the planthormones has some influence of secondary importance on the floweringprocess in Lemna. (Received January 29, 1986; Accepted July 12, 1986) 相似文献
59.
Immunological characterization of sn-1,2-diacylglycerol and sn-2-monoacylglycerol kinase from pig brain 总被引:4,自引:0,他引:4
Rabbit antisera were raised against diacylglycerol kinase purified from pig brain cytosol. Upon immunoblot analysis, the antibody was specifically reactive with the kinase (Mr = 79,000-80,000). Pig brain cytosol, microsomal, and synaptosomal fractions all contained the immunoreactive Mr = 80,000 polypeptide, thus showing that the same enzyme is present in the soluble as well as membrane fractions of the brain. The antibody could precipitate only 60% of the kinase activity present in the crude cytosol. Further, the antibody exhibited very little or no cross-reactivity toward liver cytosolic enzymes obtained from different animals including pigs. Immunostaining of brain tissues demonstrated that neurons, in particular, their nuclei, were positively stained, whereas glial cells were not stained. It is likely that there exists a tissue-and/or cell-dependent immunological multiplicity of diacylglycerol kinase. The enzyme activities phosphorylating sn-1 and sn-2 monoacylglycerols were co-precipitated by the antibody, indicating their identity with diacylglycerol kinase. The enzyme activity toward sn-1 monoolein was much lower than that obtained with sn-2 monoolein. Enzymic as well as chemical analyses of acyl isomers of the reaction products showed that even tested with pure (greater than 95%) sn-1 monoolein, about 70% of the formed lysophosphatidate was of the sn-2 acyl type. The results show that diacylglycerol kinase phosphorylates almost exclusively the sn-2 acyl type of monoacyl-glycerol. 相似文献
60.
The frequency distribution of the fork length of 0+ aged masu salmon,Oncorhynchus masou, changed from unimodal to bimodal distribution in autumn of the years from 1982 to 1984 in the Mogusa River of southern Hokkaido, Japan. The bimodal distribution consists of two (upper and lower) modal groups. These two groups resulted from a difference in growth rate of 0+ aged individuals in autumn. Fish belonging to the upper modal group are assumed to be potential 1+ smolts. Whether 0+ aged parr transform into smolt or remain as parr in the following spring may be related to the growth rate of fish in the first autumn. 相似文献