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1.
Int J Syst Evol Microbiol ; 59(Pt 12): 2977-86, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19643890

RESUMO

Three novel bacterial strains, PVAS-1(T), B3W22(T) and B8W22(T), were isolated from cryotubes used to collect air samples at altitudes of between 27 and 41 km. Based on phenotypic characteristics, chemotaxonomic features, DNA-DNA hybridization with the nearest phylogenetic neighbours and phylogenetic analysis based on partial 16S rRNA gene sequences (PVAS-1(T), 1196 nt; B3W22(T), 1541 nt; B8W22(T), 1533 nt), the three strains were identified as representing novel species, and the names proposed are Janibacter hoylei sp. nov. (type strain PVAS-1(T) =MTCC 8307(T) =DSM 21601(T) =CCUG 56714(T)), Bacillus isronensis sp. nov. (type strain B3W22(T) =MTCC 7902(T) =JCM 13838(T)) and Bacillus aryabhattai sp. nov. (type strain B8W22(T) =MTCC 7755(T) =JCM 13839(T)).


Assuntos
Actinomycetales/classificação , Actinomycetales/isolamento & purificação , Microbiologia do Ar , Ar/análise , Bacillus/isolamento & purificação , Equipamentos e Provisões/microbiologia , Actinomycetales/genética , Bacillus/classificação , Bacillus/genética , DNA Bacteriano/genética , DNA Ribossômico/genética , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética
2.
Int J Syst Evol Microbiol ; 56(Pt 7): 1465-1473, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16825614

RESUMO

Four novel bacterial strains were isolated from cryogenic tubes used to collect air samples at altitudes of 24, 28 and 41 km. The four strains, 24K(T), 28K(T), 41KF2a(T) and 41KF2b(T), were identified as members of the genus Bacillus. Phylogenetic analysis based on 16S rRNA gene sequences indicated that three of the strains, 24K(T), 28K(T) and 41KF2a(T), are very similar to one another (>98 % sequence similarity) and show a similarity of 98-99 % with Bacillus licheniformis and 98 % with Bacillus sonorensis. DNA-DNA hybridization studies showed that strains 24K(T), 28K(T) and 41KF2a(T) exhibit <70 % similarity with each other and with B. licheniformis and B. sonorensis. Differences in phenotypic and chemotaxonomic characteristics between the novel strains and B. licheniformis and B. sonorensis further confirmed that these three isolates are representatives of three separate novel species. Strain 41KF2b(T) showed 100 % 16S rRNA gene sequence similarity to Bacillus pumilus, but differed from its nearest phylogenetic neighbour in a number of phenotypic and chemotaxonomic characteristics and showed only 55 % DNA-DNA relatedness. Therefore, the four isolates represent four novel species for which the names Bacillus aerius sp. nov. (type strain, 24K(T)=MTCC 7303(T)=JCM 13348(T)), Bacillus aerophilus sp. nov. (type strain, 28K(T)=MTCC 7304(T)=JCM 13347(T)), Bacillus stratosphericus sp. nov. (type strain, 41KF2a(T)=MTCC 7305(T)=JCM 13349(T)) and Bacillus altitudinis sp. nov. (type strain, 41KF2b(T)=MTCC 7306(T)=JCM 13350(T)) are proposed.


Assuntos
Microbiologia do Ar , Altitude , Bacillus/classificação , Bacillus/isolamento & purificação , Antibacterianos/farmacologia , Bacillus/química , Bacillus/genética , Bacillus/fisiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , Temperatura Baixa , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácidos Graxos/análise , Ácidos Graxos/isolamento & purificação , Genes de RNAr/genética , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
3.
Electrophoresis ; 16(9): 1775-81, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8582371

RESUMO

The discovery of the structure DNA at the beginning of this half of the century, and the recognition that it is virtually the universal genetic material, made it imperative for man, sooner or later, to apply this knowledge for unexpected ends. Genetic engineering, DNA fingerprinting, sequencing of whole genomes (be they of man, plants or microorganisms), or exploitation of the differences between the DNA of the male and the female (for example, of the X and the Y sperm) have thus all been historical imperatives. Today, many such predicted technologies are a reality or have come close to being so. Such DNA-based technologies have enormous social implications, discussed in this article. The impact of these technologies on different societies is likely to be different, in view of the different social conditions that prevail, and the different historical background and cultural traditions. In India, for example, the use of DNA fingerprinting could prevent the large-scale exploitation of women, and several kinds of litigation. On a global scale, the availability of this technique and its refinement to a stage where it would become virtually foolproof could act as a deterrent to certain kinds of crime. There will also be unprecedented benefits to agriculture but also new problems that will need to be faced and resolved. Wisdom demands that we prepare ourselves for a large-scale application of the new DNA technologies that are a historical imperative, understand the problems that are likely to arise, and plan to cope with them before they descend on us in full force.


Assuntos
Impressões Digitais de DNA , Responsabilidade Social , Agricultura , Feminino , Medicina Legal , Engenharia Genética , Humanos , Masculino , Paternidade
4.
Biochim Biophys Acta ; 1221(2): 109-14, 1994 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-8148387

RESUMO

Seminal plasmin, an antimicrobial and transcription-inhibitory protein of bovine seminal plasma, is shown to lyse dividing mammalian cells in vitro. It lyses cells in culture such as CHO, Vero, HeLa and L929. It also lyses regenerating rat liver parenchymal cells and cells of two ascitic tumours of rat--the Zajdela ascitic hepatoma and the AK-5. However, it does not lyse resting cells such as adult liver parenchymal cells, erythrocytes, or resting lymphocytes, though it binds to their cell surface. It can be used, therefore, to distinguish cells that are in the division cycle from cells that are in the resting phase. The cell-lytic activity of seminal plasmin is inhibited by Ca2+.


Assuntos
Morte Celular/efeitos dos fármacos , Proteínas/farmacologia , Sêmen/metabolismo , Proteínas Secretadas pela Vesícula Seminal , Sequência de Aminoácidos , Animais , Células CHO , Bovinos , Divisão Celular , Linhagem Celular , Cricetinae , Haplorrinos , Células HeLa , Humanos , Camundongos , Dados de Sequência Molecular , Peptídeos/síntese química , Peptídeos/farmacologia , Ratos , Células Vero
5.
Biochem Int ; 26(1): 125-33, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1377468

RESUMO

RNAase SPL, a ribonuclease isolated earlier from bovine seminal plasma, was shown to possess the ability to produce large acid-insoluble fragments of Mg(2+)-containing RNA in a limit digest. The factor which could be responsible for this apparent specificity has been identified as polyvinyl sulphate; it has been shown that polyvinyl sulphate inhibits RNAase SPL at much lower concentrations than required for RNAase A. The earlier results are now reinterpreted based on this effect of polyvinyl sulphate, thus providing a plausible explanation for RNAase SPL's apparent specificity. RNAase SPL has been shown to be a mixture of two ribonucleases, RNAase SPL I and RNAase SPL II. RNAase SPL I is like RNAase A in its activity while RNAase SPL II, the major ribonuclease in seminal plasma, appears to be identical to RNAase BS1.


Assuntos
Endorribonucleases/metabolismo , RNA Bacteriano/metabolismo , Sêmen/enzimologia , Sequência de Aminoácidos , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Endorribonucleases/química , Endorribonucleases/isolamento & purificação , Magnésio/farmacologia , Masculino , Dados de Sequência Molecular , Polivinil/farmacologia , RNA Bacteriano/isolamento & purificação , Especificidade por Substrato
6.
World J Microbiol Biotechnol ; 8(3): 227-8, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-24425467
7.
J Gen Microbiol ; 136(3): 463-9, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1697323

RESUMO

Two temperature-sensitive autolysis-defective mutants of Escherichia coli were isolated and shown to be resistant to lysis induced by seminalplasmin, an antimicrobial protein from bovine seminal plasma, as well as to lysis induced by ampicillin, D-cycloserine and nocardicin, at 37 or 42 degrees C but not at 30 degrees C. The mutants were, however, sensitive to inhibition of RNA synthesis by seminalplasmin even at the nonpermissive temperature. Temperature-resistant revertants of the mutants were sensitive to lysis induced by the various antibiotics at 37 or 42 degrees C. The mutations in both strains were mapped at 58 min on the E. coli linkage map. The lysis resistance of the mutants was phenotypically suppressed by the addition of NaCl. Partial suppression of the lysis-resistant phenotype was also observed in a relA genetic background.


Assuntos
Escherichia coli/genética , Lactamas , Mutação , Proteínas/farmacologia , Proteínas Secretadas pela Vesícula Seminal , Resistência a Ampicilina , Antibacterianos/farmacologia , Autólise , Mapeamento Cromossômico , Ciclosserina/farmacologia , Elementos de DNA Transponíveis , Resistência Microbiana a Medicamentos , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Fenótipo , RNA Bacteriano/biossíntese , Cloreto de Sódio/farmacologia
8.
Appl Environ Microbiol ; 55(3): 767-70, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2930174

RESUMO

Ten cultures of Pseudomonas spp. were established from soil samples collected in and around a lake in Antarctica. Based on their morphology, biochemical and physiological characteristics, and moles percent G + C of their DNA, they were identified as P. fluorescens, P. putida, and P. syringae. This is the first report on the identification of Pseudomonas spp. from continental Antarctica.


Assuntos
Pseudomonas/isolamento & purificação , Microbiologia do Solo , Regiões Antárticas , Contagem de Colônia Microbiana , Meios de Cultura , Pseudomonas/crescimento & desenvolvimento , Pseudomonas/metabolismo
9.
Cell Mol Biol ; 35(3): 285-91, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2673521

RESUMO

Using IgG antibodies raised against RNA-A BS1, the presence of this seminal RNA-A on the surface of bovine spermatozoa has been demonstrated. Indirect immunofluorescence and immunoferritin methods showed that this protein coats the surface of ejaculated bovine spermatozoa, but the pattern of binding of the label varied from cell to cell. More than 50% of the spermatozoa showed labelling all over, except the anterior head region; about 30% showed labelling all over except the region below the equatorial plate region; and the remaining were either completely labelled or showed labelling only in the head or the tail region. The head-tail junction (the neck region) was not labelled in any case.


Assuntos
Endorribonucleases/análise , Espermatozoides/enzimologia , Animais , Bovinos , Imunofluorescência , Masculino , Microscopia Eletrônica , Cabeça do Espermatozoide/enzimologia , Cabeça do Espermatozoide/ultraestrutura , Cauda do Espermatozoide/enzimologia , Cauda do Espermatozoide/ultraestrutura , Espermatozoides/ultraestrutura
10.
Biosci Rep ; 8(6): 519-29, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3242639

RESUMO

The problem of regulation of cell division is essentially a problem of understanding regulation of transition from the resting state of a cell to the dividing state and vice versa. In malignancy the ability to revert back to a normal resting state is impaired. A model is presented which attempts to explain the control of the above transitions through control of uptake of essential nutrients by a transport-inhibitory protein. Experimental evidence in favour of the model is given.


Assuntos
Divisão Celular , Transformação Celular Neoplásica , Animais , Interfase , Fígado/citologia , Fígado/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Modelos Biológicos , Proteínas de Neoplasias/metabolismo , Proteínas/metabolismo , Ratos
13.
J Gen Microbiol ; 133(5): 1265-71, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-2443610

RESUMO

Seminalplasmin, an antimicrobial protein from bovine seminal plasma, lysed both Gram-positive and Gram-negative bacteria but not Candida albicans. The lytic activity was not lysozyme-like and was not affected by inhibitors of RNA or protein synthesis or by azide; it was strongly inhibited by divalent cations like Ca2+, Mn2+ and Mg2+ at millimolar concentrations. Maximum lysis of Escherichia coli was obtained at 37 degrees C; heat treatment of E. coli drastically reduced its susceptibility to lysis by seminalplasmin. E. coli cells in the stationary phase of growth were lysed much less than those in the exponential phase, and those grown in an enriched medium were lysed much more than those grown in a minimal medium. It appears that the lytic activity of seminalplasmin is due to the activation of an autolysin.


Assuntos
Antibacterianos/farmacologia , Bacteriólise/efeitos dos fármacos , Proteínas/farmacologia , Proteínas Secretadas pela Vesícula Seminal , Bacillus subtilis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Cinética , RNA Bacteriano/biossíntese
14.
Comput Appl Biosci ; 2(3): 189-94, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2466542

RESUMO

A simple computer program has been developed to locate repeating subsequences of all possible lengths in a given nucleic acid. The observed number of repeats of subsequences was compared with the expected number of such repeats in several RNAs. The analysis showed that, in the case of rRNAs, there are no constraints in the choice of the fourth and the higher order nucleotides, while the selection is maximum at the level of nearest neighbour. This is, however, not true for RNAs coding for proteins, where the constraints are also found at the level of nucleotides containing five or more bases.


Assuntos
Microcomputadores , Oligorribonucleotídeos/análise , Sequências Repetitivas de Ácido Nucleico , Software , Algoritmos , RNA Bacteriano , RNA Ribossômico 16S , RNA Ribossômico 23S
15.
FEBS Lett ; 201(2): 233-6, 1986 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-2423370

RESUMO

The sequence of seminalplasmin, a basic antimicrobial and transcription-inhibitory protein from bovine seminal plasma, has been determined using an automated sequenator. This sequence is slightly different from that reported earlier by Theil and Scheit [(1983) EMBO J. 2, 1159-1163] and identical with that of caltrin, a Ca2+-transport-inhibitory protein of bovine seminal plasma. Caltrin and seminalplasmin are, therefore, the same protein.


Assuntos
Proteínas , Sêmen/análise , Proteínas Secretadas pela Vesícula Seminal , Sequência de Aminoácidos , Animais , Anti-Infecciosos , Bovinos , Cromatografia Líquida de Alta Pressão , Masculino , Inibidores da Transcriptase Reversa
17.
Microbios ; 45(183): 105-12, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-2423852

RESUMO

Seminalplasmin, a 6,000 dalton antimicrobial protein present in bovine seminal plasma, is shown to inhibit growth and/or RNA synthesis in several bacterial species. In only one strain out of twenty one belonging to fourteen species, did both RNA synthesis and growth appear to be resistant to seminalplasmin. The antibacterial activity of seminalplasmin, in the case of E. coli, was also studied as a function of its concentration and of time; the minimal concentration of the protein required for 100% bactericidal activity was only about twice that required for 100% bacteriostatic activity. The killing of E. coli cells proceeded in two phases, a slow phase and then a rapid one, and required several hours for completion. Several bacterial species tested secreted proteases into the medium that destroyed seminalplasmin.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Proteínas/farmacologia , Proteínas Secretadas pela Vesícula Seminal , Animais , Bacillus subtilis/efeitos dos fármacos , Bactérias/enzimologia , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Bovinos , Enterobacteriaceae/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/metabolismo , Cinética , Masculino , Peptídeo Hidrolases/metabolismo , Proteínas/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , RNA Bacteriano/biossíntese , Sêmen , Staphylococcus aureus/efeitos dos fármacos
18.
Biochem J ; 227(2): 609-19, 1985 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-2408604

RESUMO

The isolation from bovine seminal plasma and purification of a new protein called 'antiseminalplasmin', which reverses the inhibition of the growth of, and RNA synthesis in, Escherichia coli by seminalplasmin (another protein of bovine seminal plasma), is described. Antiseminalplasmin, a weakly acidic protein, has a minimum Mr of about 39 000 and appears to consist of three acidic peptide chains that move close to each other on electrophoresis on cellulose acetate strips or on sodium dodecyl sulphate/18%-(w/v)-polyacrylamide gels. Antiseminalplasmin has a tendency to oligomerize at slightly alkaline pH values; it does not bind to seminalplasmin or to DNA, and does not reverse the inhibition by seminalplasmin of transcription in vitro by purified E. coli RNA polymerase. It appears that antiseminalplasmin may act by binding to the cell surface and preventing the entry of seminalplasmin into the cells. By itself, antiseminalplasmin has no effect on the growth of E. coli.


Assuntos
Proteínas/farmacologia , Proteínas Secretadas pela Vesícula Seminal , Cromatografia em Gel , Eletroforese , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Focalização Isoelétrica , Peptídeo Hidrolases , Poli U/metabolismo , Proteínas/isolamento & purificação , RNA/biossíntese , Ribonuclease Pancreático/metabolismo , Ribonucleases , Transcrição Gênica
20.
J Biochem ; 97(2): 463-71, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3891745

RESUMO

Seminalplasmin, an antimicrobial protein present in bovine seminal plasma, is shown to inhibit the growth of, as well as nucleic acid and protein synthesis in, wild-type Saccharomyces cerevisiae SM202, when used at concentrations greater than 200 micrograms/ml, in contrast to 20 micrograms/ml that is sufficient for Escherichia coli. An osmotically labile strain of S. cerevisiae VY1160 is 1-2 orders of magnitude more sensitive to seminalplasmin than the wild-type strain. RNA synthesis in protoplasts and nuclei of S. cerevisiae SM 202 was also about as sensitive to seminalplasmin as in E. coli and S. cerevisiae VY1160. The RNA polymerases I and II from S. cerevisiae were strongly inhibited by seminalplasmin in vitro, while DNA and protein syntheses were not affected by seminalplasmin in cell-free systems, unlike in the whole cells. It is concluded that seminalplasmin acts in S. cerevisiae by entering the cells and inhibiting transcription.


Assuntos
Anti-Infecciosos/farmacologia , DNA Fúngico/biossíntese , Proteínas Fúngicas/biossíntese , Proteínas/farmacologia , RNA Fúngico/biossíntese , Saccharomyces cerevisiae/efeitos dos fármacos , Proteínas Secretadas pela Vesícula Seminal , Antibacterianos , Núcleo Celular/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Mitocôndrias/metabolismo , Proteínas/classificação , Protoplastos/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Transcrição Gênica
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