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31.
Amine oxidases have been purified to homogeneity from Pisum sativum, Lens esculenta, Lathyrus sativus and Cicer arietinum. The enzymes have a Mr. of 150 000 and are composed of two identical subunits of 72 000. The amine oxidases showed an isoelectrophoretic heterogeneity. 相似文献
32.
Phenylarsine oxide induces the cyclosporin A-sensitive membrane permeability transition in rat liver mitochondria 总被引:2,自引:0,他引:2
Ewa Lenartowicz Paolo Bernardi Giovanni Felice Azzone 《Journal of bioenergetics and biomembranes》1991,23(4):679-688
This paper reports an investigation on the effects of the hydrophobic, bifunctional SH group reagent phenylarsine oxide (PhAsO) on mitochondrial membrane permeability. We show that PhAsO is a potent inducer of the mitochondrial permeability transition in a process which is sensitive to both the oxygen radical scavanger BHT and to cyclosporin A. The PhAsO-induced permeability transition is stimulated by Ca2+ but takes place also in the presence of EGTA in a process that maintains its sensitivity to BHT and cyclosporin A. Our findings suggest that, at variance from other known inducers of the permeability transition, PhAsO reacts directly with functional SH groups that are inaccessible to hydrophilic reagents in the absence of Ca2+. 相似文献
33.
The role of the pro-sequence in the processing and secretion of the thermolysin-like neutral protease from Bacillus cereus 总被引:5,自引:0,他引:5
The Bacillus cereus cnp gene coding for the thermolysin-like neutral protease (TNP) has been cloned, sequenced, and expressed in Bacillus subtilis. The protease is first produced as a pre-pro-protein (M(r) = 61,000); the pro-peptide is approximately two-thirds of the size of the mature protein. The pro-sequence has been compared with those of six other TNPs, and significant homologies have been found. Additionally, the TNP pro-sequences are shown to be homologous to the pro-sequence of Pseudomonas aeruginosa elastase. A mutant has been constructed from cnp, in which 23 amino acids upstream from the pro-protein processing site have been deleted. This region has no homologous analogue in any of the other TNP pro-sequences. The deletion results in a delay of six to eight hours in detection of active protease in the growth medium, as well as a 75% decrease in maximum protease production. N-terminal analysis of the mutant mature protein demonstrates that the processing site is unaltered by the pro-sequence deletion. The deletion must, therefore, modulate the kinetics of processing and/or secretion of the pro-protein. 相似文献
34.
35.
Identification of an insertion sequence, IS1081, in Mycobacterium bovis 总被引:12,自引:0,他引:12
Abstract: An insertion sequence, IS1081, in the genome of Mycobacterium bovis has been identified and sequenced. It is 1324 bp long with 15 bp inverted repeat ends and contains a large ORF. There are six copies of IS1081 in the genome of M. bovis and the element is also present in Mycobacterium tuberculosis . IS1081 is not closely related to other DNA elements described in actinomycetes but its putative transposase bears some resemblance to that of IS256 from Staphylococcus aureus . IS1081 may be useful for genetic manipulations and for developing a diagnostic test for bovine tuberculosis based on the polymerase chain reaction. 相似文献
36.
Cloning and characterization of an extracellular temperature-labile serine protease gene from Aeromonas hydrophila 总被引:6,自引:0,他引:6
Octavio Rivero Juan Anguita Diana Mateos Carmen Paniagua Germán Naharro 《FEMS microbiology letters》1991,81(1):1-7
Aeromonas virulence is thought to depend on multigenic functions. The gene for an extracellular protease from Aeromonas hydrophila SO2/2 was cloned in Escherichia coli C600-1 by using pIJ860, bifunctional plasmid, as a vector. The gene encodes for a temperature-labile serine protease (P2) with a molecular mass of approx. 68 kDa which is highly inhibited by PMSF. The gene was expressed in Streptomyces lividans 1326 by transforming protoplasts with the original clone pPA2. We were also able to transfer and express the prt P2 gene in Pseudomonas putida by mating experiments. The protein P2 was secreted into the periplasms of both P. putida and E. coli C600-1 being identical in properties to one of the proteases secreted into the culture supernatant by A. hydrophila SO2/2. 相似文献
37.
Carmelo B. Bruni M. Stella Carlomagno Silvestro Formisano Giovanni Paolella 《Molecular & general genetics : MGG》1986,203(3):389-396
Summary A detailed comparative analysis of the Escherichia coli and Salmonella typhimurium hisIE and hisD gene products and the functionally equivalent, single, HIS4 gene product of Saccharomyces cerevisiae permitted several insights concerning the relationship between these genes. Our analysis supports the idea that HIS4 results from the fusion of hisIE and hisD. The comparison permitted a more precise definition of the functional domains of hisI/HIS4A and hisE/HIS4B as well as the two functional domains of hisD/HIS4C. The homologies between the bacterial and yeast sequences suggest a region of the hisD/HIS4C protein that may constitute one of the active centres. A large fragment at the amino terminal region of the yeast protein is missing from the bacterial hisIE gene product and is probably not needed for catalytic activity. Another region of non-homology in the yeast protein is probably a peptide bridge connecting the HIS4AB domain to HIS4C. Although the overall homology at the level of amino acid sequence is modest (about 38%) there is a striking similarity when the hydropathic patterns and predicted secondary structural configurations of these proteins are compared. 相似文献
38.
Sergio Sgorbati Marisa Levi Elio Sparvoli Federica Trezzi Giovanni Lucchini 《Physiologia plantarum》1986,68(3):471-476
Cytometry and flow cytometry were used to study characteristics of fluorescence of the DNA-DAPI complex in nuclei released from different fresh and formaldehyde-fixed pea ( Pisum sativum L. cv. Lincoln) tissues. The two methods of isolation are compared and discussed as well as their possible use for quantitative analysis of DNA in plant tissues. With fixed tissues it is possible to obtain a number of nuclei sufficient for the flow cytometric analysis, even using small amounts of plant tissue. 相似文献
39.
Milzani Aldo; Carrera Paolo; Bergna Giovanni; Colombo Roberto 《Bioinformatics (Oxford, England)》1986,2(1):19-22
A program in BASIC is described which allows accurate quantificationof some numerical parameters that can be objectively correlatedto biological indexes in sigmoid biological events. Attentionwas focused on the polymerization process of actin (a muscleprotein with a mol. wt of 42 000 daltons) studied as the variationin the OD360 index with time. The experimental points, if plotted,can be well approximated by a rational function of the typeOD360 = f(t), which passes through the origin and can be representedgraphically by a sigmoid curve. The program was very helpfulin comparing the experimental curves and in analysing significantparameters, such as maximum velocity and asymptote, that characterizethese curves and whose interpretation would otherwise be purelysubjective.
Received on July 11, 1985; accepted on January 13, 1986 相似文献
40.
John T. Christeller Betty E. Terzaghi Diana F. Hill W. A. Laing 《Plant molecular biology》1985,5(4):257-263
Summary The ribulose bisphosphate carboxylase/oxygenase (EC4.1.1.39) (RubisCO) large and small subunit genes from Anacystis nidulans have been cloned as a single fragment into M 13mp10 and pEMBL8 and expressed in Escherichia coli. From M 13mp10 a low yield of enzyme with high specific activity was obtained. The molecular weight of the active enzyme was 260 000 Da and of the inactive enzyme approximately 730 000 Da. The small and large subunits cloned separately did not express activity. The RubisCO gene cloned into pEMBL8 expressed activity up to 22 times that from the M 13 cloned RubisCO DNA. The RubisCO protein produced by the pEMBL cloned gene had a normal MW (550 000). Immunoprecipitation and polyacrylamide gel electrophoresis showed the presence of both large and small subunits. 相似文献