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51.
Book Review
Progress in botanyH.-D. Behnke, K. Esser, K. Kubitzki, M. Runge and H. Ziegler (Eds.), 50. Berlin: Springer-Verlag, 1989. XIX+386 pages. DM 258.00. ISBN 3-540-50289-0 相似文献52.
Comparison of a commercial biochemical kit and an oligonucleotide probe for identification of environmental isolates of Vibrio vulnificus 总被引:3,自引:0,他引:3
A. DALSGAARD, I. DALSGAARD, L. HØI AND J.L. LARSEN. 1996. Methods for the identification and isolation of environmental isolates of Vibrio vulnificus were evaluated. Alkaline peptone water supplemented with polymyxin B and colistin-polymyxin B-cellobiose agar were employed for the isolation of suspected V. vulnificus from water, sediment and shellfish samples. When comparing the identification of putative V. vulnificus obtained with the API 20E assay and an oligonucleotide probe, 29 API 20E profiles were obtained with only four profiles (representing 20 isolates) reaching the identification threshold of V. vulnificus among a total of 66 isolates hybridizing with the probe. The results indicated that, compared with colony hybridization, the API 20E assay was not adequate for the identification of environmental isolates of V. vulnificus . 相似文献
53.
Miodrag Petrović Ilijana Grigorov Tanja Milosavljević Desanka Bogojević Snežana Ŝekularac Ljiljana Ševaljević 《Molecular biology reports》1996,23(2):79-85
A 29 kD soluble rat liver nucleoprotein (p29) has increased binding affinity for the hormone responsive element (RE) of the rat haptoglobin (Hp) gene during the acute-phase reaction. In this work the possibility of its structural and functional homology to the high mobility group 1 (HMG1) nonhistone protein constituent of chromatin was examined. The results of two-dimensional gel electrophoresis, Southwestern and Western immunoblot analyses, showed that p29 and HMG1 are homologous protein species. On the basis of in vitro and in vivo phosphorylation/dephosphorylation experiments, we discuss the modulatory role of phosphate groups in view of the structure and function of p29. 相似文献
54.
The effect of the growth form of the inducing microorganism on specificTrichoderma harzianum mycolytic enzyme production was studied. The pelleted form ofRhizopus nigricans gave a better product concerning protoplast formation ability. The maximum yield of protoplasts from the target fungusCochliobolus lunatus was 1×108 ml–1. Analysis of individual specific enzyme activities inTrichoderma mycolytic enzyme preparations confirms the importance of high chitinase and low protease activity for high protoplast yields. Supplementation of the production medium with chitin increased the chitinase activity in theTrichoderma exoenzyme mixture. 相似文献
55.
Photosynthesis inhibition in algae (Chlorella) and plant (spinach) chloroplasts by quaternary ammonium salts of heptacaine {N-[2-(2-heptyloxyphenylcarbamoyloxy)-ethyl]-N-alkylpiperidinium
bromides} depended on the alkyl chain length of the alkyl substituent and showed good correlations with theoretical hydrophobic
fragment constants as well as with experimentally determined physico-chemical parameters, namely extraction constants and
surface activities.
Communicated by. Z. ŠESTáK 相似文献
56.
Escherichia coli was isolated from the urine of patients with pyelonephritis, with urinary tract infections other than pyelonephritis and
with asymptomatic bacteriuria. Surface properties of the strains were analyzed by the salting-out aggregation test (SAT),
hydrophobic interaction chromatography (HIC), Congo red binding (Crb), agglutination of erythrocytes (MRHA) and latex particles
covered by digalactoside (PF) and by adherence to tissue culture cells. In addition, a DNA probe for thepap gene was used. The DNA probe detected the highest proportion of strains withpap gene in the group of patients with pyelonephritis, lower in the urinary tract infections other than pyelonephritis and the
lowest in the group with asymptomatic bacteriuria. Tests for P-fimbriae (PF, MRHA) showed a similar distribution. Hydrophobicity
measured by SAT and by HIC did not show differences among the tested groups of strains. The results suggest that factors other
than the P-fimbriae and hydrophobicity may contribute to the persistence ofE. coli in the urinary tract. 相似文献
57.
Escherichia coli is the common causative agent of urinary tract infections. Sixty-one strains ofE. coli isolated from children with urinary tract infections were tested by colony hybridization for the presence of genes determining P and S fimbriae and hemolysin. Of these strains, 46 possess a gene for hemolysin, 44 for P fimbriae and 28 for S fimbriae. Only 30 strains formed lytic zones around the colonies on plates with sheep erythrocytes. The results indicated that simultaneous occurrence of genes in urinaryE. coli was highest for P fimbriae and hemolysin and lower for other combinations of the tested genes. 相似文献
58.
Matjana Didek-Brumec Vladimira Gaberc-Porekar Marija Alačević Helena Sočič 《Applied microbiology and biotechnology》1993,38(6):746-749
Protoplasts of morphologically and biochemically different Claviceps purpurea strains producing ergotoxins were fused without introducing selective auxotrophic markers. Fused strains thus obtained differed significantly in biosynthetic activity and morphology from the prototrophic isolates obtained after fusion of the same parent strains marked by auxotrophy. Comparison of the two types of fused strains showed about tenfold higher alkaloid production in fusants obtained from prototrophic strains. Selected stable prototrophic isolates also showed a significant productivity improvement in comparison with the original parent strains.
Correspondence to: M. Didek-Brumec 相似文献
59.
本研究首次发现了毛鹃花芽分化过程中的一个特殊现象──秋季侧花芽伸长生长现象。并认为充足的光照,适宜的气温(25°─26℃)及充沛的降水伴随较高的空气相对湿度是导致这种花芽伸长生长的主要环境因子。也进一步证实了毛鹃是一类较喜阳生生境的灌木花卉。 相似文献
60.
从印度木薯花叶病毒(ICMV)侵染的植物中纯化特异的核酸,经RNAase,DNAasc,Nucle-aseSl,ExonucleaseⅢ和EcoRI酶切,Southern和Dotblots杂交证实,在感病的植株中,存在两种形式的病毒核酸:环状双链DNA和环状单链DNA,后者可能是病毒DNA的(-)链,环状双链DNA经限制性内切酶作用可得2.7kb的线性双链DNA纯化的病毒核酸含DNA1和DNA2两个分子量相近的组份。 相似文献