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41.
Kanji Ishizaki Asao Noda Mituo Ikenaga Kenji Ida Keiichi Omoto Yusuke Nakamura Ken-ichi Matsubara 《Human genetics》1985,71(3):261-262
Summary The plasmid clone which contains human salivary amylase cDNA was used to detect restriction fragment length polymorphisms
(RFLPs). After double digestion with Pst 1 and Bam H1, a polymorphism with two alleles was observed. In Japanese, frequencies of these alleles, tentatively called 5.7kb and 6.5kb
fragment alleles, are 0.55 and 0.45, respectively. 相似文献
42.
Mechanism-based inactivators were used to probe the active site of the broad specificity amino acid racemase from Pseudomonas striata. Kinetic parameters for the inactivation of the racemase with both stereoisomers of beta-fluoroalanine, beta-chloroalanine, and O-acetylserine were determined. By use of 14C-labeled O-acetylserines, the stoichiometry of inactivator binding was found to be one inactivator bound per enzyme subunit. The PLP-dependent enzyme contains one coenzyme per subunit, and after NaB3H4 reduction of the PLP-imine bond, followed by trypsin digestion of the protein, the amino acid sequence of the PLP-binding peptide was determined. Trypsin digestion of the enzyme labeled with either L or D isomer of O-acetylserine and sequencing of the labeled peptide revealed that the inactivators bind to the same lysine residue which binds PLP in native enzyme. The characterization of a PLP adduct released from inactivated enzyme under some conditions is also described. Implications of the formation of this compound with respect to the overall reaction mechanism of inactivation are discussed. 相似文献
43.
Kenji Hayasaka Yoshi Kawamoto Takayoshi Shotake Ken Nozawa 《Primates; journal of primatology》1986,27(1):103-114
We calculated the probability of paternity exclusion (P) in 6 troops of rhesus and Japanese macaques housed in open enclosures and 68 wild troops of Japanese, crab-eating, and toque
macaques using 33 genetic loci which encoded the blood protein variations detected by electrophoretic techniques. In the open
enclosures, especially of rhesus troops, we obtained a fairly high probability of paternity exclusion and succeeded in determining
the fathers of offspring. However, we found significant differences between the observed and calculated probabilities in most
of the troops. These differences were ascribed to a situation whereby the Hardy-Weinberg equilibrium had not been attained
in the troops and/or the numbers of variable loci were too small. In the wild troops of Japanese, crab-eating, and toque macaques,
the means ofP were 0.2274 (0.0192–0.5017), 0.4635 (0.1676–0.7151), and 0.7382 (0.6266–0.7954), respectively. We also estimated the number
of loci needed to determine the fathers of offspring with a probability of 0.8 assuming that ten males were present in the
troop. The estimated number was about 13.5 times, 5 times and 1.8 times the number of loci examined on average in the troops
of Japanese, crab-eating and toque macaques, respectively. This means that determination of most of the fathers of offspring
in wild troops of these macaques, even of toque macaques which have a rather high probability of paternity exclusion, is difficult
so long as we employ only electrophoretic techniques. 相似文献
44.
N Shinohara H Tanaka T Saito J Deguchi K Soda T Sugiyama Y Ishimaru S Sonoda 《Japanese journal of medical science & biology》1983,36(3):191-197
Eighty-two cases of typhoid fever were found in Matsuyama city in the period from 1974 to 1981. Seventy-six cases were found to be infected with Salmonella typhi other three with Salmonella paratyphi A, and the remaining three were diagnosed only clinically. The strains of S. typhi isolated from these patients showed such a variety of Vi-phage types as D1, D2, E1, M1, 53 and degraded Vi-positive strain (DVS). The concurrent survey of the city sewage and river waters for typhoid bacilli was conducted with total 578 samples taken therefrom. S. typhi was isolated from 120 of those samples. The Vi-phage types of the isolates were closely related with those of the isolates from the patients. The periodical examinations of the city sewage and the draining river may serve as a useful means for the controlling typhoid fever epidemics. 相似文献
45.
A number of epoxides, including cis- and trans-stilbene oxides, were assayed as substrates for epoxide hydrolases (EHs) by gas-liquid chromatography. Radiolabeled stilbene oxides were prepared by sodium borotritide reduction of desyl chloride followed by ring closure with base treatment. Rapid radiometric assays for EHs were performed by differential partitioning of the epoxide into dodecane, while the product diol remained in the aqueous phase. Glutathione (GSH) transferase was similarly assayed by partitioning the epoxide and diol, if formed metabolically, into 1-hexanol, while the GSH conjugate was retained in the aqueous phase. The cytosolic EH rapidly hydrates the trans isomer while the cis is very poorly hydrated. In contrast, the cis is a better substrate for the microsomal EH than the trans. GSH transferase utilized both epoxides as substrates, but conjugation is faster with the cis isomer. Cytosolic EH activity is high in mouse but very low in rat and guinea pig. Microsomal EH activity, in contrast, is highest in guinea pig, intermediate in rat, and the lowest in mouse. GSH transferase activity, which is high in all three species, can be inhibited by chalcone, with an I50 of 3.1 × 10?5m. These assays facilitate the rapid evaluation and direct comparison of epoxide-metabolizing systems in cell homogenates used in short-term mutagenicity assays, cell or organ culture, and possibly in vivo. 相似文献
46.
Solaniol, a Toxic Metabolite of Fusarium solani 总被引:7,自引:6,他引:1
Kenji Ishii Kosei Sakai Yoshio Ueno Hiroshi Tsunoda Makoto Enomoto 《Applied microbiology》1971,22(4):718-720
Fusarium solani M-1-1 isolated from moldy bean hulls produces T-2 toxin, diacetoxyscirpenol, and a new toxic trichothecene, solaniol, in Czapek-Dox-peptone medium. 相似文献
47.
48.
49.
Formation of Recombinants Between Nontransmissible Drug-Resistance Determinants and Transfer Factors 总被引:5,自引:2,他引:3
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Susumu Mitsuhashi Mitsuo Kameda Kenji Harada Mitsue Suzuki 《Journal of bacteriology》1969,97(3):1520-1521
Noninfectious drug-resistance determinants acquired conjugal transmissibility by the formation of recombinants with transfer factors, suggesting the origin of R factors. 相似文献
50.
Crystalline amino acid racemase with low substrate specificity 总被引:1,自引:0,他引:1