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1.
Staphylococcal gamma-hemolysin and leukocidin are bi-component cytolysins, consisting of LukF (or Hlg1)/Hlg2 and LukF/LukS, respectively. Here, we purified serum inhibitors of gamma-hemolysin and leukocidin from human plasma. Protein sequencing showed that the purified inhibitors of 62, 57, 50 and 38 kDa were the vitronectin fragments with truncation(s) of the C-terminal or both N- and C-terminal regions. The purified vitronectin fragments specifically bound to the Hlg2 component of gamma-hemolysin and the LukS component of leukocidin to form high-molecular-weight complexes with them, leading to inhibition of the toxin-induced lysis of human erythrocytes and human polymorphonuclear leukocytes, respectively. Intact vitronectin also showed inhibitory activity to the toxins. The ability of gamma-hemolysin and leukocidin to bind vitronectin and its fragments is a novel function of the pore-forming cytolysins. 相似文献
2.
Summary An activated carbon column was utilized for the synthesis of disaccharides by use of a reversed hydrolysis activity of an immobilized -galactosidase column in order to shift the equilibrium to the direction of condensation. The yields of lactulose and allo-lactulose from galactose and fructose, and N-acetyl lactosamine and N-acetyl allolactosamine from galactose and N-acetyl glucosamine, were 11.3% and 10.0%, respectively. 相似文献
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4.
Pro----leu change at position 102 of prion protein is the most common but not the sole mutation related to Gerstmann-Str?ussler syndrome 总被引:20,自引:0,他引:20
K Doh-ura J Tateishi H Sasaki T Kitamoto Y Sakaki 《Biochemical and biophysical research communications》1989,163(2):974-979
The host-encoded prion protein (PrP) is a component of transmissible amyloid deposited in the brains affected by Gerstmann-Str?ussler syndrome (GSS). Recently GSS in two unrelated Caucasian families has been reported to be linked to an amino acid change in PrP codon 102, proline to leucine (Leu102). However, it has not been clear whether the change is commonly found to GSS regardless of ethnic origin. We report here that Leu102 is also found in all the Japanese GSS patients tested. Interestingly, one French GSS patient was found to have another change, alanine to valine in codon 117 (Val117), instead of Leu102. Our results indicate that Leu102 is closely related to GSS irrespective of ethnic origin, but not the sole mutation related to GSS. Val117 may also be related to GSS. 相似文献
5.
Katsumi Togashi 《Population Ecology》1988,30(2):177-192
Summary The seasonal occurrence ofMonochamus alternatus and newly weakened trees were investigated in aPinus thunbergii stand for 4 years. Adult beetles were present between June and September with a peak in their population occurring in early
July followed by a decline then a period of about one month being in a steady number. The average number ofBursaphelenchus xylophilus (Nematoda), which is the causal agent of pine wilt disease, within beetles decreased as the season advanced. Pine trees newly
weakened byB. xylophilus appeared between June and October, especially from August to October. The proportion of weakened or killed trees was directly
proportional to the average beetle density per tree from June to August. 相似文献
6.
Satoh Hiroyuki; Okada Mitsumasa; Nakayama Katsumi; Murata Teruyo 《Plant & cell physiology》1985,26(5):931-940
Ribulose 5-phosphate (Ru5P) kinase (ATP:D-ribulose 5-phosphate1-phosphotrans- ferase; EC 2.7.1.19
[EC]
), an enzyme in the reductivepentose phosphate cycle, was purified from the green alga Bryopsismaxima and its activity and peptide composition were studied.The specific activity of purified Ru5P kinase was 20 µmoleRuBP formed (mg protein)1 min1 corresponding toa 490-fold purification from the supernatant of chloroplasts.The Km values of Ru5P kinase for ATP and Ru5P were 69 µMand 330 µM, respectively. The molecular size of Ru5P kinase was estimated as 90 kDa bygel filtration and that of its polypeptide as 41 kDa by SDS-polyacrylamidegel electrophoresis. A small portion of the Ru5P kinase wasfound in a large molecular state (500 kDa) which was consideredto be an inactive form of the enzyme. Ru5P kinase activity has been reported in the pyrenoid of Eremosphaeraviridis as well as ribulose 1,5-bisphosphate carboxylase-oxygenase(RuBisCO) and ribose 5-phosphate isomerase activity (Holdsworth1971). In Bryopsis maxima, among the pyrenoid polypeptides otherthan that of RuBisCO, we found a polypeptide of 42 kDa, similarto that of Ru5P kinase in molecular size and ratio to RuBisCO.A peptide map of the 42 kDa pyrenoid polypeptide, however, showedthat it differed from that of Ru5P kinase. In conclusion, Ru5Pkinase may be not involved in the pyrenoid of this alga. (Received January 19, 1985; Accepted May 15, 1985) 相似文献
7.
Green Lavandula vera callus that produced biotin was preservedsuccessfully in liquid nitrogen for up to 3 weeks. We foundthat the callus recovered after the freeze-preservation, retainingnot only the biosynthetic capability for biotin but also differentiationpotentials such as chloroplast development and plantlet formation.The significance of retention of the metabolic and differentiationpotentials of the callus is discussed in terms of the freeze-preservationof plant genetic resources.
* This study is dedicated to the late Professor J. Ashida. (Received September 1, 1982; Accepted November 5, 1982) 相似文献
8.
9.
Ryousuke Takahashi Katsumi Kawamura Jianguo Hu †Michiyuki Hayashi Takeo Deguchi 《Journal of neurochemistry》1996,67(2):525-529
Abstract: To study the level of ciliary neurotrophic factor (CNTF) in human nervous tissues, we developed a sensitive enzyme-linked immunoassay using a specific antibody against human CNTF. This method allowed us to detect as little as 0.3 ng/ml of human CNTF with good linearity and accuracy. Using this method, CNTF levels were determined in human sciatic nerves obtained at autopsy from 21 amyotrophic lateral sclerosis (ALS) patients and 48 subjects who had died of other neurological diseases. CNTF genotypes were also determined. The results indicated that CNTF levels were high in the normal homozygotes and approximately halved in the heterozygote subjects. There was, however, no significant difference in CNTF levels in the sciatic nerves between ALS and other neurological disease patients, indicating that the CNTF level was mainly determined by its genotypes and that the level in the sciatic nerves was not reduced in ALS patients. 相似文献
10.
Neutral red (NR) in the culture medium entered the vacuolesof a green alga, Micrasterias pinnatifida, at a higher rateat pH 8 than at pH 5. NR remained soluble in vacuoles of cellscultured at pH 5, while it precipitated and formed granulesin cells cultured at pH 8. The vacuoles of cells cultured atpH 8 contained fibrils, but those of cells cultured at pH 5did not. The amount of NR that entered the cells was markedlyreduced by the addition to the medium of nigericin at 10-5M,monensin at 10-5M, bafilo-mycin A1 at 10-5M, or ammonium chlorideat 50 mM. The formation of NR granules in vacuoles were stronglyinhibited and the disorganization of NR granules were acceleratedby the addition of nigericin at 10-5M, or bafilomycin A1 at10-5M to the culture medium. The possibility is discussed thatNR which enters vacuoles might become positively charged (NRH+)by protons brought into vacuoles by proton pumps and that NRH+might combine with some negatively charged macromolecules toform aggregates or granules. (Received April 18, 1996; Accepted May 27, 1996) 相似文献