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61.
We explore the relationship between transition probabilities in the Leslie model and those derived from experimental cumulative distributions. The nature of the two kinds of probabilities are discussed, and a formula derived for converting from one to the other. A numerical example is given to illustrate the differences. 相似文献
62.
DNA fragments which are intrinsically bent or curved migrate anomalously during electrophoresis through polyacrylamide gels. Starting with an initial population of approximately 10(12) unique DNA sequences, DNA which exhibited the kind of anomalous mobility associated with DNA bending was selected and enriched using a variation of the SELEX procedure. After seven rounds of selection and amplification, the vast majority of the remaining population of DNA fragments migrated as bent DNA. Cloning and sequencing of 30 individual sequences from this population has yielded information regarding the relationship between DNA sequence and bending. Some of the previous conclusions on DNA bending have been confirmed while others have been modified, by the results presented here. In addition, the dinucleotide base step CA/TG, which had not been thought to be a major factor in DNA bending, appears to be important. 相似文献
63.
R. Shane Gold M. M. Meagher R. Hutkins T. Conway 《Journal of industrial microbiology & biotechnology》1992,10(1):45-54
Summary This paper describes the ethanol tolerance and metabolism of 31 strains ofLactobacillus on glucose, xylose, lactose, cellobiose and starch. The purpose of this work was to determine the suitability of the 31 strains as potential host for the ethanol producing genes, pyruvate decarboxylase and aldehyde dehydrogenase, fromZymomonas mobilis. The 31 strains were screened for their ability to grow in 0 to 8% v/v ethanol on all five carbohydrates. Those strains that were able to grow to an OD of 1.0 in 8% ethanol were evaluated at ethanol concentrations up to 16%. v/v. The fermentative products from the five carbohydrates were analyzed to determine the ratios of lactic acid, ethanol, and acetic acid.Published as Paper No. 9786, Journal Series Nebraska Agricultural Experiment Station, Lincoln, NE 68583-0704. 相似文献
64.
Use of the 'Perceptron' algorithm to distinguish translational initiation sites in E. coli. 总被引:48,自引:22,他引:26 下载免费PDF全文
We have used a "Perceptron" algorithm to find a weighting function which distinguishes E. coli translational initiation sites from all other sites in a library of over 78,000 nucleotides of mRNA sequence. The "Perceptron" examined sequences as linear representations. The "Perceptron" is more successful at finding gene beginnings than our previous searches using "rules" (see previous paper). We note that the weighting function can find translational initiation sites within sequences that were not included in the training set. 相似文献
65.
66.
Britta Swebilius Singer Larry Gold Sidney T. Shinedling Michelle Colkitt Lawrence R. Hunter David Pribnow Mary Anne Nelson 《Journal of molecular biology》1981,149(3):405-432
We have mapped the mutants isolated by Nelson et al. (1981) that reduce the amount of rIIB protein synthesized during bacteriophage T4 infection of Escherichia coli B and characterized their rIIB expression in vivo. These mutants fall into four distinct groups in terms of mapping and phenotype. We have located the probable site of each mutation on the DNA sequence. We have also analyzed a number of other mutations near the initiating AUG of rIIB with respect to their rIIB expression. In some of these mutants, ribosomal recognition of the wild-type initiating AUG is precluded and so initiation occurs at a different AUG, which, in some instances, we have identified. 相似文献
67.
Observations were done on the effect of inorganic substances on the gut evacuation process in Daphnia magna. Procedures which accelerate this process are described. 相似文献
68.
D M Haverstick D Dickemper A H Gold 《Biochemical and biophysical research communications》1979,87(1):177-183
Cycloheximide given to insulin-treated alloxan diabetic rats results in the inhibition of insulin-induced liver glycogen synthase conversion without affecting the level of synthase . The effect of cycloheximide, believed to elevate cAMP in liver of normal rats, is independent of cAMP levels of the insulin-treated diabetic rat. The inhibition of insulin-mediated synthase to conversion by cycloheximide does not appear to be the result of a cycloheximide-induced cAMP-dependent phosphorylation of synthase to and suggests that insulin control of synthase and interconversions is dependent upon cycloheximide-sensitive protein synthesis. 相似文献
69.
Alvin H. Gold David Dickemper Doris M. Haverstick 《Molecular and cellular biochemistry》1979,25(1):47-59
Summary Liver glycogen synthase b phosphatase, chromatographically separable from phosphorylase a phosphatase, is decreased in 48-hour alloxan diabetic rats. The phosphatase activities are measured in an in vitro system using exogenous isolated phospho-enzyme as substrates with added phosphatases. Synthase and phosphorylase phosphatases were shown to have differential catalytic properties by their reactivity in the presence of Pi, the heat-stable inhibitor of phosphorylase phosphatase and after incubation with added cAMP-dependent protein kinase.Supported by NIH Grants HD-07788, AM-21149 and, in part, by grants from the Greater St. Louis Diabetic Childrens Welfare Association and the American Diabetes Association, N.Y. 相似文献
70.
In Phanerochaete chrysosporium fruit body formations is subject to strong catabolite repression by glucose in the presence of physiological levels of nitrogen. Walseth cellulose was found to be the best source of carbon for the induction of fruit body and consequent basidiospore synthesis. Ejected basidiospores collected from cultures grown under these conditions for two weeks are contaminated with neither conidia nor mycelial fragments and are therefore suitable for genetic analysis of recombination. Under conditions of nitrogen limitation, the glucose catabolite repression of fruit body synthesis was relieved. Exogenous adenosine 3,5-monophosphate but not other related nucleotides, also relieved glucose catabolite repression of fruit body formation. 相似文献