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41.
Growth requirements of hyperthermophilic sulfur-dependent heterotrophic archaea isolated from a shallow submarine geothermal system with reference to their essential amino acids. 总被引:8,自引:1,他引:7 下载免费PDF全文
T Hoaki M Nishijima M Kato K Adachi S Mizobuchi N Hanzawa T Maruyama 《Applied microbiology》1994,60(8):2898-2904
Three hyperthermophilic sulfur-dependent heterotrophs were isolated from a shallow submarine hydrothermal system at an inlet of Kodakara-jima island, Kagoshima, Japan. The isolates grew at 60 to 97 degrees C, with the optimum temperatures at 85 to 90 degrees C. Sensitivity to rifampin and the existence of ether lipids indicated that the isolates are hyperthermophilic archaea. Partial sequencing of the genes coding for 16S rRNA showed that the three isolates are closely related to the genus Thermococcus. They grew on proteinaceous mixtures, such as yeast extract, Casamino Acids, and purified proteins (e.g., casein and gelatin), but not on carbohydrates or organic acids as sole carbon and energy sources. Nine amino acids were essential for growth of isolate KS-1 (Thr, Leu, Ile, Val, Met, Phe, His, Tyr, and Arg). Isolate KS-2 required Lys in addition to the nine amino acids, and KS-8 required Lys instead of Tyr. In comparative studies, it was shown that Thermococcus celer DSM 2476 required 10 amino acids (Thr, Leu, Ile, Val, Met, Phe, Tyr, Trp, Lys, and Arg) while Pyrococcus furiosus DSM 3638 required only Ile and Val. The hyperthermophilic fermentative eubacterium Thermotoga neapolitana DSM 4359 did not require any amino acids for growth. 相似文献
42.
Koichi Suzuki Misa Iwata Shigenori Ito Kiyoshi Matsui Atsuko Uchida Yasuhiko Mizoi 《Human genetics》1994,94(2):129-135
The “a” subunit of human coagulation factor XIII (F13A) exhibits genetic polymorphism defined by four common alleles, F13A*1A, *1B, *2A, and *2B. We have previously suggested on the basis of the isoelectric focusing patterns of the four allele products that point mutations at two separate sites and one intragenic crossing over might be involved in the genes of F13A polymorphism. Here, we report nucleotide substitutions associated with F13A polymorphism. A C/T transition of the second nucelotide of codon 564 in exon 12 is responsible for the difference between F13A*1A and *1B and that between F13A*2A and *2B, and a set of two base changes in codons 650 and 651 in exon 14 leads to the differences between F13A*1A and *2A and those between F13A*1B and *2B. The four combinations of the point mutations at the two exons thus correspond to the four alleles, two of which were generated by the point mutations from ancestral monomorphic gene. The results suggest strongly that intragenic crossing over must be involved in the genesis of the fourth allele. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods discriminating these base changes in exons 12 and 14 are also presented. 相似文献
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Safak Yalcin Hirohiko Kuratsune Koji Yamaguchi Teruo Kitani Koichi Yamanishi 《Microbiology and immunology》1994,38(7):587-590
Peripheral blood mononuclear cells collected from 13 patients with chronic fatigue syndrome and 13 healthy controls were analyzed for the presence of human herpesvirus 6 (HHV-6) DNA by variant-specific polymerase chain reaction and dot blot hybridization. HHV-6 DNA was detected in 7 of 13 (53%) patients, and of those 7 patients, 4 were positive for HHV-6 variant A DNA and 3 were for variant B. No HHV-6 DNA was detected in the controls. Serum antibody titers to the late antigen and antibody prevalence to the early antigen of HHV-6 were significantly higher in the patient group. These results suggest active replication of HHV-6 in patients with chronic fatigue syndrome. 相似文献
45.
Hirai Nobuhiro; Kojima Yasuhiro; Koshimizu Koichi; Shinozaki Masateru; Takimoto Atsushi 《Plant & cell physiology》1993,34(7):1039-1044
Flowering of Pharbitis nil strain Violet is induced in continuouslight under poor nutritional conditions. High-performance liquidchromatography of extracts of the cotyledons revealed that twocompounds in addition to chlorogenic acid accumulate under suchconditions. The compounds were identified as pinoresinol glucosideand p-coumaroylquinic acid. The endogenous levels of these phenylpropanoidswere correlated with the flowering response when nutrition waspoor. However, activation of phenylpropanoid biosynthesis seemednot to be essential for the induction of flowering. (Received May 17, 1993; Accepted July 26, 1993) 相似文献
46.
Koichi Ohshima Masahiro Kikuchi Shinichi Kobari Yuichi Masuda Fuyuki Eguchi Nobuhiro Kimura 《Virchows Archiv. B, Cell pathology including molecular pathology》1993,63(1):197-198
Using the polymerase chain reaction (PCR) to examine the occurrence ofbcl-2/JH joining produced by t(14;18) chromosomal translocation, amplified DNA was detected in 2 of 18 lymph nodes showing reactive
lymphadenopathy. The PCR was repeated in these two lymphs nodes using the same DNA samples, but no amplification was detected
at the second attempt. Thus the amplified DNA was considered to be derived from one copy of joinedbcl-2/JH in one cell, or from a few copies in a few clonal cells with the same joinedbcl-2/JH. These results suggest that false joining ofbcl-2/JH at the t(14;l8) junction may occur in reactive lymph nodes. 相似文献
47.
48.
Kensuke Nakanishi Nao Hasegawa Koichi Takeo Keisuke Nakajima Nobuaki Furuno Ichiro Tazawa 《Development, growth & differentiation》2023,65(2):100-108
Some frog species have a unique skeletal element, referred to as the intercalary element (IE), in the joints between the terminal and subterminal phalanges of all digits. IEs are composed of cartilage or connective tissue and have a markedly differ shape than the phalanges. IEs are highly related to the arboreal lifestyle and toe pads. The IE is found only in neobatrachian frogs among anurans, suggesting that it is a novelty of Neobatrachia. IEs are widely distributed among multiple neobatrachian lineages and are found in the suborders Hyloides and Ranoides (the two major clades in Neobatrachia). However, it is unclear whether the IEs found in multiple linages resulted from convergent evolution. Therefore, in this study, we aimed to examine how similar or different the developmental trajectories of the IEs are between Hyloides and Ranoides. To that end, we compared the osteological and histological developmental processes of the IEs of the hyloid frog Dryophytes japonicus and the ranoid frog Zhangixalus schlegelii. Both species shared the same IE-initiation site and level of tissue differentiation around the IE when it began to form in tadpoles, although the IE developments initiated at different stages which were determined by external criteria. These results suggest that similar mechanisms drive IE formation in the digits of both species, supporting the hypothesis that the IEs did not evolve convergently. 相似文献
49.
Noriko Takahashi Katsuyoshi Masuda Kenji Hiraki Kazuo Yoshihara Hung-Hsiang Huang Kay-Hooi Khoo Koichi Kato 《European journal of biochemistry》2003,270(12):2627-2632
To determine the glycoforms of squid rhodopsin, N-glycans were released by glycoamidase A digestion, reductively aminated with 2-aminopyridine, and then subjected to 2D HPLC analysis [Takahashi, N., Nakagawa, H., Fujikawa, K., Kawamura, Y. & Tomiya, N. (1995) Anal. Biochem.226, 139-146]. The major glycans of squid rhodopsin were shown to possess the alpha1-3 and alpha1-6 difucosylated innermost GlcNAc residue found in glycoproteins produced by insects and helminths. By combined use of 2D HPLC, electrospray ionization-mass spectrometry and permethylation and gas chromatography-electron ionization mass spectrometry analyses, it was revealed that most (85%) of the N-glycans exhibit the novel structure Manalpha1-6(Manalpha1-3)Manbeta1-4GlcNAcbeta1-4(Galbeta1-4Fucalpha1-6)(Fucalpha1-3)GlcNAc. 相似文献
50.
A new gobiid species,Acanthogobius insularis, is described from 88 specimens collected from Amami-oshima Island and Okinawa Island, Ryukyu Islands, southern Japan. The
species is distinguished from its congeners by the combination of dorsal and anal fin ray counts, vertebral counts, cephalic
sensory system patterns and coloration. 相似文献