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T Kanaji H Ozaki T Takao H Kawajiri H Ide M Motoki Y Shimonishi 《Canadian Metallurgical Quarterly》1993,268(16):11565-11572
The complete amino acid sequence of transglutaminase (EC 2.3.2.13) (TGase), which is produced by a microorganism, Streptoverticillium sp. strain s-8112, and catalyzes the acyl transfer reaction between gamma-carboxyamide groups of glutamine residues in proteins and various primary amines, has been established by a combination of fast atom bombardment mass spectrometry and standard Edman degradation of peptide fragments produced by treatment of the TGase with various proteolytic enzymes and purified by a reversed-phase high performance liquid chromatography. The TGase consists of 331 amino acid residues with a chemical molecular weight of 37,863, in agreement with the observed molecular weight (37,869.2 +/- 8.8) determined from its electrospray ionization mass spectrum. The sequence of the enzyme is very different from those of mammalian TGases represented by guinea pig liver enzyme. The enzyme contains a sole Cys residue, which is essential for its catalytic activity. Hydropathy analysis indicated that the secondary structure of the region around the active site Cys residue is similar to those of mammalian TGases. These results suggest that this microbial protein evolved by a different pathway from that of mammalian TGases and acquired acyl transfer activity during the evolutional process. 相似文献
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AH Sarker S Ikeda H Nakano H Terato H Ide K Imai K Akiyama K Tsutsui Z Bo K Kubo K Yamamoto A Yasui MC Yoshida S Seki 《Canadian Metallurgical Quarterly》1998,282(4):761-774
The association patterns between maternal anthropometric characteristics (stature, prepregnancy weight, prepregnancy body mass index, pregnancy weight gain) and newborn size (birth weight, length, head circumference) were tested with 10,240 single births taking place between 1985 and 1995 in Vienna, Austria, and 3,452 single births taking place between 1989 and 1995 in Westerstede-Ammerland (Friesland), northern Germany. Maternal size and newborn size differed highly significantly (p < 0.001) between the two genetically and socioeconomically different population groups. Furthermore, the incidence of macrosomia among newborns (birth weight greater than 4000 g) was extraordinarily high (17.9%) in the Frisian group from northern Germany. In both populations taller and heavier women with a higher weight gain during pregnancy gave birth to heavier offspring. Nevertheless, the pregnancy weight gain, which indicates environmental conditions of the mother, had only a minor impact on newborn size compared with stature and prepregnancy weight, which reflect the maternal genetic potential to a higher degree. 相似文献
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This paper traces the history of the Text Encoding Initiative, through the Vassar Conference and the Poughkeepsie Principles to the publication, in May 1994, of theGuidelines for the Electronic Text Encoding and Interchange. The authors explain the types of questions that were raised, the attempts made to resolve them, the TEI project's aims, the general organization of the TEI committees, and they discuss the project's future.Nancy Ide is Associate Professor and chair of Computer Science at Vassar College, and Visiting Researcher at CNRS. She is president of the Association for Computers and the Humanities and chair of the Steering Committee of the Text Encoding Initiative. C. M. Sperberg-McQueen is a Senior Research Programmer at the academic computer center of the University of Illinois at Chicago; his interests include medieval Germanic languages and literatures and the theory of electronic text markup. Since 1988 he has been editor in chief of the ACH/ACL/ALLC Text Encoding Initiative. 相似文献
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The inhibitory effect of phosphate on acetoclastic-methanogens was investigated for three different thermophilic (55 degrees C) anaerobic consortia. When 70 mM of phosphate was tested, acetoclastic methanogens was completely inhibited in "Eerbeek" sludge which is dominated by Methanosaeta-like methanogens. For the "Hoogezand" sludge the specific methanogenic activity dropped by 79%, indicating that any of the acetate-consuming methanogens present in the sludge was more resistant to the phosphate applied. The results demonstrated that the inhibitory effect of phosphate may affect both methane production rate and final methane concentration and might also be time dependent. This study indicates that the degree of inhibition is species-dependent, and even more resistant species may be affected during long-term experiments. Such inhibition is a matter of concern for researchers since misleading conclusions might be taken from growth and specific methanogenic activity tests when considerable concentrations of phosphate buffer are used and no interference is expected. 相似文献