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31.
Sodium-dependence of glycylglycine (Gly-Gly) influx and stimulation of Na+ transport by Gly-Gly were studied in everted sacs, sheet preparations and brush-border membrane vesicles isolated from guinea-pig ileum. Gly-Gly influx was found to be independent of the presence of Na+, while Na+ transport was stimulated by Gly-Gly as evidenced by increases in transmural potential difference (PDt), short-circuit current (Isc) and Na+ influx. The change in PDt (ΔPDt) induced by Gly-Gly was a saturable function of Gly-Gly concentration, showing a Michaelis-Menten type relationship. The half-saturation concentration for Gly-Gly estimated from the electrical data was nearly identical with that estimated from influx data. At a constant Gly-Gly concentration the relationship between Isc and Na+ concentration was sigmoid, and the Hill coefficient was 1.5. Kinetic analysis according to Garay Garrahan indicates that each Gly-Gly carrier has two equivalent non-interacting binding sites for Na+, and that translocation of Na+ occurs when the two Na+ sites on the carrier loaded with Gly-Gly are occupied by Na+. However, our results indicate that the resultant Na+ flow is not capable of stimulating Gly-Gly translocation. 相似文献
32.
Phenotypic and chemotaxonomic characteristics of five isolates of acetylenereducing (nitrogen-fixing) oligotrophic bacteria from a paddy soil were investigated. They showed similar phenotypic characteristics: they were aerobic, asporogenous, gram-negative, motile by a polar flagellum, and irregular rods. On full strength nutrient broth (NB) growth was severely suppressed, but well supported on 10-to 10000-fold diluted NB. They consumed glucose but produced no acid, and also utilized phenolic acids such as ferulic acid or p-coumaric acid. The cellular fatty acid composition, quinone system and DNA base composition of the isolates were investigated. Cellular fatty acids mainly consisted of straightchain unsaturated C18 : 1 (62–81% of total fatty acids). Ubiquinone Q-10 and a high guanine-plus-cytosine content (65.1–66.0 mol%) were found. The taxonomic status of the isolates is discussed and a new genus, Agromonas, with a single species Agromonas oligotrophica sp. nov., is proposed for these isolates. The type strain of A. oligotrophica is JCM 1494. 相似文献
33.
Hiroyuki Masatomi 《Journal of Ethology》1983,1(1-2):62-69
Responding to the actions of the mate and taking somewhat fixed patterns,Grus japonensis, G. vipio, G. antigone, Anthropoides paradisea andBalearica regulorum pairs are finally led to copulation by a sequence of mating behaviours. There are slight differences in pre-copulatory behaviour patterns between the species and the female's ‘wing-spreading’, being the soliciting and key posture for copulation, differs between the genera; The female's wings are spread wide inGrus, fairly wide inAnthropoides, and are almost folded inBalearica. Post-copulatory behaviours, however, have definite species-specific characters. They usually consist of ‘head-down’ (bowing) or ‘warping’, ‘arching’, etc. immediately following the dismounting of the male inGrus. But a pair ofBalearica first keep their heads high, or gaze at each other for a while, and then show remarkable ‘ruffle-bowing’. These characteristic post-copulatory behaviours are obviously correlated with the threat displays, evolved under agonistic situations, typical to each species. 相似文献
34.
35.
Two variants of carrot (Daucus carota L. cv. MS Yonsun) celllines, which had been selected with Al-phosphate as a sole sourceof phosphorous, were characterized on their mechanisms of phosphate-utilizationfrom Al-phosphate. Both cell lines excreted citrate into themedium. The amount of citrate excretion was highly correlatedwith cell growth in the presence of Al-phosphate. There wasabout a 1 to 1 correlation between solublized-Al and excreted-citratein the medium during cell growth. These results suggest that1) the citrate could chelate with Al, at a 1 to 1 ratio, inAl-phosphate, 2) the citrate-chelated Al remains outside thecells, and 3) solublized phosphate from Al-phosphate is utilizedfor the growth of carrot cells. The characteristics of the selectedcells were very stable, since the rate of citrate-excretionshowed no change after subculturing 25 passages without Al-phosphate. (Received August 7, 1989; Accepted October 19, 1989) 相似文献
36.
Hiroyuki Tsunoda Toshio Ohshima Jun Tohyama Masayuki Sasaki Norio Sakuragawa Frank Martiniuk 《Human genetics》1996,97(4):496-499
We report a missense mutation in an adult Japanese patient with acid alpha-glucosidase (GAA) deficiency. A TC to GT transition
at nucleotides 1585–1586, was identified. This transition resulted in an amino acid substitution of Ser-529 to Val (S529V)
in exon 11. We also have demonstrated that the S529V mutation abolishes the catalytic activity of the enzyme. Our data suggest
that this mutation is the cause of the clinical manifestation known as adult-onset GAA deficiency. The missense mutation described
here is a new mutation, and the first identified in Japanese patients with GAA deficiency.
Received: 23 May 1995 相似文献
37.
Hiroyuki Yamaguchi Hitoshi Miura Kazuoki Ohsumi Takako Osaki Haruhiko Taguchi Tomoko Yamamoto Tomoko Hanawa Sachio Ogata Shigeru Kamiya 《Microbiology and immunology》1996,40(1):77-80
To determine amino acid sequences of the epitopes recognized by monoclonal antibodies (mAbs) 3C8 and 5C3 directed against Yersinia enterocolitica heat-shock protein (HSP60), a dot blot analysis was perfomed using synthesized peptides of Y. enterocolitica HSP60 such as peptides p316-342, p327-359, p340-366, p316-326, p316-321, p319-323, and p321-326 which represent positions of amino acids in Y. enterocolitica HSP60. The dot blot analysis revealed that 5C3 mAb reacted with p316-342, p316-326 and p321-326, and 3C8 mAb p316-342 and p316-326. These results indicate that the epitopes recognized by the mAbs were associated with eleven amino acids, Asp Leu Gly Gln Ala Lys Arg Val Val Ile Asn, of p316-326. The sequence homology between p316-326 of Y. enterocolitica HSP60 and the rest of the HSP60 family suggests that the five amino acids of Lys, Arg, Val, Ile and Asn, which are highly conserved in the HSP60 family, might be related with the epitope recognized by 3C8. In contrast, it was also demonstrated that three amino acids of Leu, Gly and Val, which are not well conserved in the HSP60 family, might be related to the epitope recognized by 5C3. 相似文献
38.
Aino virus (AIV; JaNAr 28 strain) 103 TCID50/0.2 ml was inoculated in the yolk sac of 8-day-old chick embryos. Recovery and titration of the virus from various organs including the central nervous system (CNS) and skeletal muscle were performed at 2, 4, 7, 10 and 13 days after inoculation (PI). AIV was systemically disseminated and proliferated even 2 days PI. The titers of the recovered virus from the CNS and from skeletal muscle was the highest at 4 days PI and declined with time, whereas hydranencephaly, arthrogryposis and cerebellar hypoplasia developed at 7 days PI and gradually progressed until 13 days PI. 相似文献
39.
Comparison of OspA Serotypes for Borrelia burgdorferi Sensu Lato from Japan,Europe and North America
Toshiyuki Masuzawa Bettina Wilske Tetsuro Komikado Hiroyuki Suzuki Hiroki Kawabata Nanao Sato Koichi Muramatsu Nobutake Sato Emiko Isogai Hiroshi Isogai Russell C. Johnson Yasutake Yanagihara 《Microbiology and immunology》1996,40(8):539-545
Sixty-one Borrelia burgdorferi sensu lato strains from various sources (ticks, human, and wild animals) in Japan and two strains from ticks in Far Eastern Russia were classified on the basis of reactivity with 16 monoclonal antibodies (mAb) to outer surface protein A (OspA) and by DNA-DNA hybridization assay. Eleven OspA serotypes (J1 to J11) were recognized among the Japanese and the Far East Russian isolates (serotypes J1 to J9 were identified as B. garinii, serotype J10 was identified as B. afzelii, and serotype J11 corresponded to B. japonica), whereas 7 OspA serotypes for North American and European isolates previously reported (Bettina Wilske et al, J. Clin. Microbiol. 31:340-350, 1993) were not observed except for OspA serotype 2 which showed identical reactivity with OspA serotype J10. This finding provides helpful information for understanding the geographical distribution of Lyme disease borrelia and the development of vaccine and diagnostic tests. In conclusion: 1. B. burgdorferi sensu stricto has not been observed in Japan, 2. Japanese B. afzelii isolates are closely related to those from Europe, 3. B. garinii isolates from Japan are highly heterogeneous and apparently different from European B. garinii isolates. 相似文献
40.
Koike Hiroyuki; Yoneyama Koichi; Kashino Yasuhiro; Satoh Kazuhiko 《Plant & cell physiology》1996,37(7):983-988
Interactions of externally added plastoquinone (PQ) derivatives(PQ0-PQ3) with the photosystem II (PSII) acceptor side wereinvestigated in PSII membrane fragments prepared from spinachby measuring the photoreduction rates of PQ derivatives at variousPQ concentrations, and the following results were obtained. From the kinetic analysis, all the PQ derivatives (PQ0-PQ3)except PQ3 were shown to accept electrons at two sites (theQB site and the PQ site) as in the case of Synechococcus vulcanusPSII particles with benzoquinone derivatives [Satoh et al. (1995)Plant Cell Physiol. 36: 597]. Affinities of PQ derivatives at the QB site increased as thelength of the isoprene side chain got longer, while those atthe PQ site were not very much different for all the PQ derivativestested in this study. The inhibitory effect of DCMU was noncompetitive, and, therefore,the affinity of PQ3 for the PQ site was determined while thatfor the QB site could not be estimated presumably due to itsfairly high affinity to the site. Based on the results obtained using PQ derivatives, the mechanismof interaction of an authentic PQ, PQ9, at the QB site is discussed. (Received May 2, 1996; Accepted July 24, 1996) 相似文献