Chitobiase
Mostrando 1-10 de 10 artigos, teses e dissertações.
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1. Produção secundária baseada no crescimento de crustáceos: aspectos metodológicos / Secondary production based on growth of crustaceans: methodological aspects
O objetivo desta tese foi estimar a produção secundária em ambientes aquáticos, com enfoque no estuário da Lagoa dos Patos (Rio Grande, RS, Brasil). Os crustáceos são dominantes no zooplâncton da região em estudo, sendo utilizados como base das análises realizadas. A produção secundária foi estimada através de modelos matemáticos e do método
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 11/03/2011
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2. Translocation of Vibrio harveyi N,N'-diacetylchitobiase to the outer membrane of Escherichia coli.
The gene encoding N,N'-diacetylchitobiase (chitobiase) of the chitinolytic marine bacterium Vibrio harveyi has been isolated. While expression of the chitobiase gene (chb) was inducible by N,N'-diacetylchitobiose in V. harveyi, it was expressed constitutively when cloned in Escherichia coli, suggesting that controlling elements are not closely linked to chb.
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3. Chitinase determinants of Vibrio vulnificus: gene cloning and applications of a chitinase probe.
To initiate study of the genetic control of chitinolytic activity in vibrios, the chitobiase gene was isolated by cloning chromosomal DNA prepared from Vibrio vulnificus. Chimeric plasmids were constructed from Sau3A I partial digests of chromosomal DNA by ligating 5 to 15-kilobase fragments into the BamHI site, i.e., in the Tcr gene, of pBR322 (Amr Tcr). Th
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4. Chitinase-overproducing mutant of Serratia marcescens.
Genetic modification of Serratia marcescens QMB1466 was undertaken to isolated mutants which produce increased levels of chitinolytic activity. After mutagenesis with ultraviolet light, ethyl methane sulfonate or N-methyl-N'-nitro-N-nitrosoguanidine, 19,940 colonies were screened for production of enlarged zones of clearing (indicative of chitinase activity)
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5. A rapid test for chitinase activity that uses 4-methylumbelliferyl-N-acetyl-beta-D-glucosaminide.
A total of 101 strains of bacteria from environmental and clinical sources, most of which were gram negative, were tested for chitobiase activity by using a filter paper spot test with 4-methylumbelliferyl-N-acetyl-beta-D-glucosaminide as the substrate. The results were compared with those obtained by a conventional plate method for chitinase activity by usi
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6. Cloning of the genes of the chitin utilization regulon of Serratia liquefaciens.
The set of genes that determine the expression of the enzymes involved in chitin degradation by Serratia liquefaciens was cloned. The role of each gene was investigated, and for the first time regulatory genes were identified in this system. The chiA and chiB genes coded for separate chitinase activities. The chiC region coded for a chitobiase activity, but
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7. Characterization of the cDNA and genomic sequence of a G protein gamma subunit (gamma 5).
A cDNA from human placenta and liver tissues that contained both sequence for the lysosomal glycosidase di-N-acetylchitobiase and sequence homologous to the gamma subunit of GTP-binding proteins was previously isolated. Here we have shown that the gamma-subunit-homologous portion of this unusual cDNA is derived from a member of the gamma-subunit multigene fa
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8. Sequence analysis of the beta-N-acetylhexosaminidase gene of Vibrio vulnificus: evidence for a common evolutionary origin of hexosaminidases.
DNA cloned from the marine bacterium Vibrio vulnificus into Escherichia coli HB101 can hydrolyze chitin oligomer analogs in the recipient. The nucleotide sequence of the cloned DNA was determined and a single long open reading frame of 2541 base pairs (initiation codon through termination codon) was found. The nucleotide sequence predicts a gene product of 8
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9. Widespread N-Acetyl-d-Glucosamine Uptake among Pelagic Marine Bacteria and Its Ecological Implications
Dissolved free and combined N-acetyl-d-glucosamine (NAG) is among the largest pools of amino sugars in the ocean. NAG is a main structural component in chitin and a substantial constituent of bacterial peptidoglycan and lipopolysaccharides. We studied the distribution and kinetics of NAG uptake by the phosphoenolpyruvate:NAG phosphotransferase systems (PTS)
American Society for Microbiology.
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10. Chitinolytic Activity in Chromobacterium violaceum: Substrate Analysis and Regulation by Quorum Sensing
Quorum sensing control mediated by N-acyl homoserine lactone (AHL) signaling molecules has been established as a key feature of the regulation of exoenzyme production in many gram-negative bacteria. In Chromobacterium violaceum ATCC 31532 a number of phenotypic characteristics, including production of the purple pigment violacein, hydrogen cyanide, antibioti
American Society for Microbiology.