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991.
Abstract Genome analysis of Pseudomonas aeruginosa was performed by digestion with rare-cutting restriction endonucleases and subsequent one- and two-dimensional field inversion gel electrophoresis (FIGE). The frequency of chromosomal recognition sites increased in the order Spe I, Dra I, Xba I, Ssp I, Nhe I. The genome size of strain PAO and the 17 IATS strains varied from 4.4 × 106 to 5.4 × 106 base pairs. Double restriction digests and two-dimensional FIGE provide a genome fingerprint which is useful for the identification and typing of the respective strains. 相似文献
992.
J. Tomkova D. Friedecky P. Vyskocilova T. Adam 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):656-660
Inosine triphosphate pyrophosphohydrolase (ITPase) catalyzing the pyrophosphohydrolysis of inosine triphosphate, deoxyinosine triphosphate and xanthosine triphosphate is involved in the metabolism and tolerance of thiopurine drugs. ITPase activity plays an important role in the prediction of toxicity to thiopurine therapy. Activities in dry blood spots were compared with fresh erythrocytes. Samples were incubated with inosine triphosphate, then inosine monophosphate was determined by a capillary electrophoresis method. Calculated enzyme activities obtained from dry blood spots were in good accordance with activity in fresh erythrocytes. 相似文献
993.
《Bioscience, biotechnology, and biochemistry》2013,77(7):1470-1472
The use of peptide mass fingerprinting with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was demonstrated to identify and phenotypically characterize toluene-degrading bacteria via biomarkers of degradation and taxonomical classification. Pseudomonas putida F1, P. mendocina KR1, and Burkholderia sp. JS150 were grown on toluene, extracted, electrophoretically separated, and analyzed by MALDI-TOF MS. Catabolic enzymes were identified and results substantiated using tandem MS. 相似文献
994.
995.
Abstract Basidiospores of several Basidiomycetes species were treated with electrophoretic techniques, comparing the different protein fractions of the soluble component of the spores wall. The electrophoretic data were elaborated to obtain dendrograms indicating the similarity degree. The method was set up and tested for its validity. The technique showed that the degree of variability within the observed species escaped any generalization, covering a broad range; it was possible to identify the varieties in dendrograms of species grown in the same/different geographical zones; the growing environment and the symbiotic host often influenced the electrophoretic pattern of the spore wall proteins and resulted in dendrograms reflecting the ecological conditions. Abbreviations: ACP, acid phosphatases; EST, esterases; UPGMA, unweighed pair‐group method using arithmetical average 相似文献
996.
Leucine aminopeptidase in sheep serum was studied by starch gel electrophoresis. Two phenotypes, A and B, were observed, of which the former was present in 70–90 % of all the sheep examined. These two phenotypes have been shown to be controlled by a single autosomal locus, with two alleles LayA and LapB . The LapA allele is dominant. The frequencies of Lap phenotypes and alleles were determined in eleven Spanish and two foreign breeds. Serum alkaline phospatase and serum leucine aminopeptidase are electrophoretically distinct. 相似文献
997.
998.
R. M. Belagaje S. G. Reams S. C. Ly W. F. Prouty 《Protein science : a publication of the Protein Society》1997,6(9):1953-1962
A general method for obtaining high-level production of low molecular weight proteins in Escherichia coli is described. This method is based on the use of a novel Met-Xaa-protein construction which is formed by insertion of a single amino acid residue (preferably Arginine or Lysine) between the N-terminal methionine and the protein of interest. The utility of this method is illustrated by examples for achieving high-level production of human insulin-like growth factor-1, human proinsulin, and their analogs. Furthermore, highly produced insulin-like growth factor-1 derivatives and human proinsulin analogs are converted to their natural sequences by removal of dipeptides with cathepsin C. 相似文献
999.
Previously published allelic frequencies at four polymorphic protein coding loci were used as a basis for examining genetic relationships among 19 European populations of Atlantic salmon, Salmo salar L.--exclusive of Baltic drainages--from the Barents Sea to Spain. The data did not support a model of distinct ancestral (e.g. Boreal and Celtic) origins, but were consistent with all populations descending from a single ancestral group within this region with genetically diverged populations drawn together through limited local migrations. 相似文献
1000.
Time-resolved photoelectric and absorption signals from oriented purple membranes immobilized in gel 总被引:11,自引:0,他引:11
Andrs Dr Pl Hargittai Jzsef Simon 《Journal of biochemical and biophysical methods》1985,10(5-6):295-300
Kinetics of photoelectric and absorption response signals were measured on samples containing oriented purple membranes immobilized in polyacrylamide gel. The orientation and aggregation states of purple membranes remain constant independently of pH and ionic strength in such samples and the gel does not influence the protom pump. The ‘gel method’ described in this study enables direct investigation of proton pump of bacteriorhodopsin and a simultaneous measurement of absorption signals within a wide range of parameters of the solution surrounding purple membranes and offers possibilities for study of other types of membranes as well. 相似文献