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1.
Enzyme Microb Technol ; 98: 86-95, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28110668

RESUMO

Janibacter sp. strain R02 (BNM 560) was isolated in our laboratory from an Antarctic soil sample. A remarkable trait of the strain was its high lipolytic activity, detected in Rhodamine-olive oil supplemented plates. Supernatants of Janibacter sp. R02 displayed superb activity on transesterification of acyl glycerols, thus being a good candidate for lipase prospection. Considering the lack of information concerning lipases of the genus Janibacter, we focused on the identification, cloning, expression and characterization of the extracellular lipases of this strain. By means of sequence alignment and clustering of consensus nucleotide sequences, a DNA fragment of 1272bp was amplified, cloned and expressed in E. coli. The resulting recombinant enzyme, named LipJ2, showed preference for short to medium chain-length substrates, and displayed maximum activity at 80°C and pH 8-9, being strongly activated by a mixture of Na+ and K+. The enzyme presented an outstanding stability regarding both pH and temperature. Bioinformatics analysis of the amino acid sequence of LipJ2 revealed the presence of a consensus catalytic triad and a canonical pentapeptide. However, two additional rare motifs were found in LipJ2: an SXXL ß-lactamase motif and two putative Y-type oxyanion holes (YAP). Although some of the previous features could allow assigning LipJ2 to the bacterial lipase families VIII or X, the phylogenetic analysis showed that LipJ2 clusters apart from other members of known lipase families, indicating that the newly isolated Janibacter esterase LipJ2 would be the first characterized member of a new family of bacterial lipases.


Assuntos
Actinobacteria/enzimologia , Actinobacteria/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Lipase/genética , Lipase/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/classificação , Clonagem Molecular , Sequência Conservada , Estabilidade Enzimática , Escherichia coli/enzimologia , Escherichia coli/genética , Esterases/classificação , Esterases/genética , Esterases/metabolismo , Expressão Gênica , Genes Bacterianos , Temperatura Alta , Concentração de Íons de Hidrogênio , Cinética , Lipase/classificação , Modelos Moleculares , Filogenia
2.
PLoS One ; 10(7): e0133723, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26214846

RESUMO

Lipolytic enzymes have attracted attention from a global market because they show enormous biotechnological potential for applications such as detergent production, leather processing, cosmetics production, and use in perfumes and biodiesel. Due to the intense demand for biocatalysts, a metagenomic approach provides methods of identifying new enzymes. In this study, an esterase designated as Est16 was selected from 4224 clones of a fosmid metagenomic library, revealing an 87% amino acid identity with an esterase/lipase (accession number ADM63076.1) from an uncultured bacterium. Phylogenetic studies showed that the enzyme belongs to family V of bacterial lipolytic enzymes and has sequence and structural similarities with an aryl-esterase from Pseudomonas fluorescens and a patented Anti-Kazlauskas lipase (patent number US20050153404). The protein was expressed and purified as a highly soluble, thermally stable enzyme that showed a preference for basic pH. Est16 exhibited activity toward a wide range of substrates and the highest catalytic efficiency against p-nitrophenyl butyrate and p-nitrophenyl valerate. Est16 also showed tolerance to the presence of organic solvents, detergents and metals. Based on molecular modeling, we showed that the large alpha-beta domain is conserved in the patented enzymes but not the substrate pocket. Here, it was demonstrated that a metagenomic approach is suitable for discovering the lipolytic enzyme diversity and that Est16 has the biotechnological potential for use in industrial processes.


Assuntos
Biodegradação Ambiental , Esterases/metabolismo , Gasolina , Metagenômica , Consórcios Microbianos , Estabilidade Enzimática , Esterases/química , Esterases/classificação , Esterases/genética , Biblioteca Gênica , Concentração de Íons de Hidrogênio , Cinética , Lipase/genética , Lipase/metabolismo , Lipólise , Consórcios Microbianos/genética , Modelos Moleculares , Filogenia , Conformação Proteica , Especificidade por Substrato , Termodinâmica
3.
PLoS One ; 10(5): e0126651, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25973851

RESUMO

A metagenomic fosmid library from bovine rumen was used to identify clones with lipolytic activity. One positive clone was isolated. The gene responsible for the observed phenotype was identified by in vitro transposon mutagenesis and sequencing and was named est10. The 367 amino acids sequence harbors a signal peptide, the conserved secondary structure arrangement of alpha/beta hydrolases, and a GHSQG pentapeptide which is characteristic of esterases and lipases. Homology based 3D-modelling confirmed the conserved spatial orientation of the serine in a nucleophilic elbow. By sequence comparison, Est10 is related to hydrolases that are grouped into the non-specific Pfam family DUF3089 and to other characterized esterases that were recently classified into the new family XV of lipolytic enzymes. Est10 was heterologously expressed in Escherichia coli as a His-tagged fusion protein, purified and biochemically characterized. Est10 showed maximum activity towards C4 aliphatic chains and undetectable activity towards C10 and longer chains which prompted its classification as an esterase. However, it was able to efficiently catalyze the hydrolysis of aryl esters such as methyl phenylacetate and phenyl acetate. The optimum pH of this enzyme is 9.0, which is uncommon for esterases, and it exhibits an optimal temperature at 40 °C. The activity of Est10 was inhibited by metal ions, detergents, chelating agents and additives. We have characterized an alkaline esterase produced by a still unidentified bacterium belonging to a recently proposed new family of esterases.


Assuntos
Bactérias/enzimologia , Proteínas de Bactérias/metabolismo , Esterases/metabolismo , Rúmen/microbiologia , Sequência de Aminoácidos , Animais , Bactérias/classificação , Bactérias/genética , Proteínas de Bactérias/genética , Bovinos , Clonagem Molecular , DNA Bacteriano/análise , DNA Bacteriano/isolamento & purificação , Escherichia coli/metabolismo , Esterases/classificação , Esterases/genética , Biblioteca Gênica , Histidina/genética , Cinética , Metagenômica , Dados de Sequência Molecular , Oligopeptídeos/genética , Filogenia , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/isolamento & purificação , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
4.
Genet Mol Res ; 12(2): 1155-67, 2013 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-23661440

RESUMO

Genetic diversity and structure were analyzed in 10 accessions belonging to Banco Ativo de Germoplasma de Capsicum located at Federal University of Piauí in northwestern Brazil that receives pepper samples grown in community gardens in various regions and Brazilian states. Selections were made from seeds of C. chinense (4 accessions), C. annuum (5 accessions), and C. baccatum (1 accession). Samples consisting of leaves were collected from 4-10 plants of each accession (a total of 85 plants). Native polyacrylamide gel electrophoresis was used to identify α- and ß-esterase polymorphisms. Polymorphism was clearly detected in 5 loci. Sixteen alleles were found at 5 α/ß-esterase loci of the three Capsicum species. In the C. chinense samples, the highest HO and HE values were 0.3625 and 0.4395, respectively, whereas in C. annuum samples, HO and HE values were 0.2980 and 0.3310, respectively; the estimated HO and HE values in C. chinense samples were higher than those detected in C. annuum samples. A deficit of homozygous individuals was found in C. chinense (FIS = -0.6978) and C. annuum (FIS = 0.7750). Genetic differentiation between C. chinense and C. annuum at these loci was high (FST = 0.1867) indicating that C. chinense and C. annuum are genetically structured species for α/ß- esterase isozymes. The esterase analysis showed high genetic diversity among the C. chinense and C. annuum samples and very high genetic differentiation (FST = 0.6321) among the C. chinense and C. annuum samples and the C. baccatum accession.


Assuntos
Capsicum/genética , Esterases/genética , Polimorfismo Genético , Alelos , Capsicum/metabolismo , Esterases/classificação , Esterases/metabolismo , Loci Gênicos , Genótipo , Isoenzimas , Fenótipo , Filogenia
5.
Rev Argent Microbiol ; 45(1): 3-12, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23560782

RESUMO

in order to isolate novel organic solvent-tolerant (OST) lipases, a metagenomic library was built using DNA derived from a temperate forest soil sample. A two-step activity-based screening allowed the isolation of a lipolytic clone active in the presence of organic solvents. Sequencing of the plasmid pRBest recovered from the positive clone revealed the presence of a putative lipase/esterase encoding gene. The deduced amino acid sequence (RBest1) contains the conserved lipolytic enzyme signature and is related to the previously described OST lipase from Lysinibacillus sphaericus 205y, which is the sole studied prokaryotic enzyme belonging to the 4.4 α/ß hydrolase subgroup (abH04.04). Both in vivo and in vitro studies of the substrate specificity of RBest1, using triacylglycerols or nitrophenyl-esters, respectively, revealed that the enzyme is highly specific for butyrate (C4) compounds, behaving as an esterase rather than a lipase. The RBest1 esterase was purified and biochemically characterized. The optimal esterase activity was observed at pH 6.5 and at temperatures ranging from 38 to 45 °C. Enzymatic activity, determined by hydrolysis of p-nitrophenyl esters, was found to be affected by the presence of different miscible and non-miscible organic solvents, and salts. Noteworthy, RBest1 remains significantly active at high ionic strength. These findings suggest that RBest1 possesses the ability of OST enzymes to molecular adaptation in the presence of organic compounds and resistance of halophilic proteins.


Assuntos
Esterases/isolamento & purificação , Lipase/isolamento & purificação , Metagenômica , Sequência de Aminoácidos , Bacillaceae/enzimologia , Proteínas de Bactérias/química , Butiratos/metabolismo , Sequência Conservada , DNA/genética , DNA/isolamento & purificação , Esterases/classificação , Alemanha , Concentração de Íons de Hidrogênio , Hidrólise , Lipase/classificação , Lipólise , Dados de Sequência Molecular , Concentração Osmolar , Filogenia , Proteínas Recombinantes/metabolismo , Sais/farmacologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Microbiologia do Solo , Solventes/farmacologia , Especificidade por Substrato , Temperatura , Árvores , Triglicerídeos/metabolismo
6.
Rev. argent. microbiol ; Rev. argent. microbiol;45(1): 3-12, mar. 2013. graf, tab
Artigo em Inglês | LILACS | ID: lil-672048

RESUMO

In order to isolate novel organic solvent-tolerant (OST) lipases, a metagenomic library was built using DNA derived from a temperate forest soil sample. A two-step activity-based screening allowed the isolation of a lipolytic clone active in the presence of organic solvents. Sequencing of the plasmid pRBest recovered from the positive clone revealed the presence of a putative lipase/esterase encoding gene. The deduced amino acid sequence (RBest1) contains the conserved lipolytic enzyme signature and is related to the previously described OST lipase from Lysinibacillus sphaericus 205y, which is the sole studied prokaryotic enzyme belonging to the 4.4 a/ß hydrolase subgroup (abH04.04). Both in vivo and in vitro studies of the substrate specificity of RBest1, using triacylglycerols or nitrophenyl-esters, respectively, revealed that the enzyme is highly specific for butyrate (C4) compounds, behaving as an esterase rather than a lipase. The RBest1 esterase was purified and biochemically characterized. The optimal esterase activity was observed at pH 6.5 and at temperatures ranging from 38 to 45 °C. Enzymatic activity, determined by hydrolysis of p-nitrophenyl esters, was found to be affected by the presence of different miscible and non-miscible organic solvents, and salts. Noteworthy, RBest1 remains significantly active at high ionic strength. These findings suggest that RBest1 possesses the ability of OST enzymes to molecular adaptation in the presence of organic compounds and resistance of halophilic proteins.


Con el fin de aislar nuevas variantes de lipasas tolerantes a solventes organicos (OST), se construyo una libreria metagenomica a partir de ADN obtenido de una muestra de suelo de bosque templado. A traves de un monitoreo en dos etapas, basado en la deteccion de actividades, se aislo un clon con actividad lipolitica en presencia de solventes organicos. La secuenciacion del plasmido pRBest recuperado del clon positivo revelo la presencia de un gen codificante de una hipotetica lipasa/esterasa. La secuencia deducida de amino acidos (RBest1) contiene los motivos conservados de enzimas lipoliticas y esta relacionada con la lipasa OST previamente descrita de Lysinibacillus sphaericus 205y, que es la unica enzima procariota estudiada perteneciente al subgrupo 4.4 de a/ß hidrolasas (abH4.04). Estudios in vivo e in vitro sobre la especificidad de sustratos de RBest1, utilizando triacil-gliceroles o p-nitrofenil-esteres, respectivamente, revelaron que la enzima es altamente especifica para compuestos butiricos (C4), comportandose como una esterasa y no como una lipasa. La esterasa RBest1 fue purificada y caracterizada bioquimicamente. La actividad optima de esterasa fue observada a pH 6,5 y las temperaturas optimas fueron entre 38 y 45 °C. Se establecio que la actividad enzimatica, determinada por hidrolisis de p-nitrofenil esteres, es afectada en presencia de diferentes solventes organicos miscibles y no miscibles, y tambien sales. Notoriamente, RBest1 permanece significativamente activa a elevadas fuerzas ionicas. Estos hallazgos sugieren que RBest1 posee la capacidad de las enzimas OST de la adaptacion molecular en presencia de compuestos organicos, asi como la resistencia de las proteinas halofilas.


Assuntos
Esterases/isolamento & purificação , Lipase/isolamento & purificação , Metagenômica , Sequência de Aminoácidos , Bacillaceae/enzimologia , Proteínas de Bactérias/química , Butiratos/metabolismo , Sequência Conservada , DNA , Esterases/classificação , Alemanha , Concentração de Íons de Hidrogênio , Hidrólise , Lipólise , Lipase/classificação , Dados de Sequência Molecular , Concentração Osmolar , Filogenia , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Microbiologia do Solo , Especificidade por Substrato , Sais/farmacologia , Solventes/farmacologia , Temperatura , Árvores , Triglicerídeos/metabolismo
7.
Rev. argent. microbiol ; Rev. argent. microbiol;45(1): 3-12, Mar. 2013. graf, tab
Artigo em Inglês | BINACIS | ID: bin-131106

RESUMO

In order to isolate novel organic solvent-tolerant (OST) lipases, a metagenomic library was built using DNA derived from a temperate forest soil sample. A two-step activity-based screening allowed the isolation of a lipolytic clone active in the presence of organic solvents. Sequencing of the plasmid pRBest recovered from the positive clone revealed the presence of a putative lipase/esterase encoding gene. The deduced amino acid sequence (RBest1) contains the conserved lipolytic enzyme signature and is related to the previously described OST lipase from Lysinibacillus sphaericus 205y, which is the sole studied prokaryotic enzyme belonging to the 4.4 a/ß hydrolase subgroup (abH04.04). Both in vivo and in vitro studies of the substrate specificity of RBest1, using triacylglycerols or nitrophenyl-esters, respectively, revealed that the enzyme is highly specific for butyrate (C4) compounds, behaving as an esterase rather than a lipase. The RBest1 esterase was purified and biochemically characterized. The optimal esterase activity was observed at pH 6.5 and at temperatures ranging from 38 to 45 °C. Enzymatic activity, determined by hydrolysis of p-nitrophenyl esters, was found to be affected by the presence of different miscible and non-miscible organic solvents, and salts. Noteworthy, RBest1 remains significantly active at high ionic strength. These findings suggest that RBest1 possesses the ability of OST enzymes to molecular adaptation in the presence of organic compounds and resistance of halophilic proteins.(AU)


Con el fin de aislar nuevas variantes de lipasas tolerantes a solventes organicos (OST), se construyo una libreria metagenomica a partir de ADN obtenido de una muestra de suelo de bosque templado. A traves de un monitoreo en dos etapas, basado en la deteccion de actividades, se aislo un clon con actividad lipolitica en presencia de solventes organicos. La secuenciacion del plasmido pRBest recuperado del clon positivo revelo la presencia de un gen codificante de una hipotetica lipasa/esterasa. La secuencia deducida de amino acidos (RBest1) contiene los motivos conservados de enzimas lipoliticas y esta relacionada con la lipasa OST previamente descrita de Lysinibacillus sphaericus 205y, que es la unica enzima procariota estudiada perteneciente al subgrupo 4.4 de a/ß hidrolasas (abH4.04). Estudios in vivo e in vitro sobre la especificidad de sustratos de RBest1, utilizando triacil-gliceroles o p-nitrofenil-esteres, respectivamente, revelaron que la enzima es altamente especifica para compuestos butiricos (C4), comportandose como una esterasa y no como una lipasa. La esterasa RBest1 fue purificada y caracterizada bioquimicamente. La actividad optima de esterasa fue observada a pH 6,5 y las temperaturas optimas fueron entre 38 y 45 °C. Se establecio que la actividad enzimatica, determinada por hidrolisis de p-nitrofenil esteres, es afectada en presencia de diferentes solventes organicos miscibles y no miscibles, y tambien sales. Notoriamente, RBest1 permanece significativamente activa a elevadas fuerzas ionicas. Estos hallazgos sugieren que RBest1 posee la capacidad de las enzimas OST de la adaptacion molecular en presencia de compuestos organicos, asi como la resistencia de las proteinas halofilas.(AU)


Assuntos
Esterases/isolamento & purificação , Lipase/isolamento & purificação , Metagenômica , Sequência de Aminoácidos , Bacillaceae/enzimologia , Proteínas de Bactérias/química , Butiratos/metabolismo , Sequência Conservada , DNA/genética , DNA/isolamento & purificação , Esterases/classificação , Alemanha , Concentração de Íons de Hidrogênio , Hidrólise , Lipase/classificação , Lipólise , Dados de Sequência Molecular , Concentração Osmolar , Filogenia , Proteínas Recombinantes/metabolismo , Comércio/farmacologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Microbiologia do Solo , Solventes/farmacologia , Especificidade por Substrato , Temperatura , Árvores , Triglicerídeos/metabolismo
8.
Rev. argent. microbiol ; 45(1): 3-12, 2013 Jan-Mar.
Artigo em Espanhol | BINACIS | ID: bin-133185

RESUMO

in order to isolate novel organic solvent-tolerant (OST) lipases, a metagenomic library was built using DNA derived from a temperate forest soil sample. A two-step activity-based screening allowed the isolation of a lipolytic clone active in the presence of organic solvents. Sequencing of the plasmid pRBest recovered from the positive clone revealed the presence of a putative lipase/esterase encoding gene. The deduced amino acid sequence (RBest1) contains the conserved lipolytic enzyme signature and is related to the previously described OST lipase from Lysinibacillus sphaericus 205y, which is the sole studied prokaryotic enzyme belonging to the 4.4 α/ß hydrolase subgroup (abH04.04). Both in vivo and in vitro studies of the substrate specificity of RBest1, using triacylglycerols or nitrophenyl-esters, respectively, revealed that the enzyme is highly specific for butyrate (C4) compounds, behaving as an esterase rather than a lipase. The RBest1 esterase was purified and biochemically characterized. The optimal esterase activity was observed at pH 6.5 and at temperatures ranging from 38 to 45 °C. Enzymatic activity, determined by hydrolysis of p-nitrophenyl esters, was found to be affected by the presence of different miscible and non-miscible organic solvents, and salts. Noteworthy, RBest1 remains significantly active at high ionic strength. These findings suggest that RBest1 possesses the ability of OST enzymes to molecular adaptation in the presence of organic compounds and resistance of halophilic proteins.


Assuntos
Esterases/isolamento & purificação , Lipase/isolamento & purificação , Metagenômica , Sequência de Aminoácidos , Bacillaceae/enzimologia , Proteínas de Bactérias/química , Butiratos/metabolismo , Sequência Conservada , DNA/genética , DNA/isolamento & purificação , Esterases/classificação , Alemanha , Concentração de Íons de Hidrogênio , Hidrólise , Lipase/classificação , Lipólise , Dados de Sequência Molecular , Concentração Osmolar , Filogenia , Proteínas Recombinantes/metabolismo , Comércio/farmacologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Microbiologia do Solo , Solventes/farmacologia , Especificidade por Substrato , Temperatura , Árvores , Triglicerídeos/metabolismo
9.
Mem Inst Oswaldo Cruz ; 107(4): 437-49, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22666852

RESUMO

The use of chemical insecticides continues to play a major role in the control of disease vector populations, which is leading to the global dissemination of insecticide resistance. A greater capacity to detoxify insecticides, due to an increase in the expression or activity of three major enzyme families, also known as metabolic resistance, is one major resistance mechanisms. The esterase family of enzymes hydrolyse ester bonds, which are present in a wide range of insecticides; therefore, these enzymes may be involved in resistance to the main chemicals employed in control programs. Historically, insecticide resistance has driven research on insect esterases and schemes for their classification. Currently, several different nomenclatures are used to describe the esterases of distinct species and a universal standard classification does not exist. The esterase gene family appears to be rapidly evolving and each insect species has a unique complement of detoxification genes with only a few orthologues across species. The examples listed in this review cover different aspects of their biochemical nature. However, they do not appear to contribute to reliably distinguish among the different resistance mechanisms. Presently, the phylogenetic criterion appears to be the best one for esterase classification. Joint genomic, biochemical and microarray studies will help unravel the classification of this complex gene family.


Assuntos
Esterases/classificação , Inativação Metabólica/genética , Resistência a Inseticidas/genética , Animais , Esterases/química , Esterases/genética , Filogenia
10.
Mem. Inst. Oswaldo Cruz ; 107(4): 437-449, June 2012. ilus
Artigo em Inglês | LILACS | ID: lil-626435

RESUMO

The use of chemical insecticides continues to play a major role in the control of disease vector populations, which is leading to the global dissemination of insecticide resistance. A greater capacity to detoxify insecticides, due to an increase in the expression or activity of three major enzyme families, also known as metabolic resistance, is one major resistance mechanisms. The esterase family of enzymes hydrolyse ester bonds, which are present in a wide range of insecticides; therefore, these enzymes may be involved in resistance to the main chemicals employed in control programs. Historically, insecticide resistance has driven research on insect esterases and schemes for their classification. Currently, several different nomenclatures are used to describe the esterases of distinct species and a universal standard classification does not exist. The esterase gene family appears to be rapidly evolving and each insect species has a unique complement of detoxification genes with only a few orthologues across species. The examples listed in this review cover different aspects of their biochemical nature. However, they do not appear to contribute to reliably distinguish among the different resistance mechanisms. Presently, the phylogenetic criterion appears to be the best one for esterase classification. Joint genomic, biochemical and microarray studies will help unravel the classification of this complex gene family.


Assuntos
Animais , Esterases/classificação , Resistência a Inseticidas/genética , Inativação Metabólica/genética , Esterases/química , Esterases/genética , Filogenia
11.
Genetica ; 137(1): 111-24, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19301127

RESUMO

Esterases are known for their involvement in several physiological processes and high degree of polymorphism, in many organisms. Such polymorphism has been used to characterize species and species groups and to study genetic changes occurred in their evolutionary history. In the present study, the esterase patterns of 19 strains from 10 species representative of the five subgroups of the saltans species group were analyzed using polyacrylamide gel electrophoresis and alpha- and beta- naphthyl acetates as substrates. Fifty-one esterase bands were detected and classified as 31 alpha-esterases, 18 beta-esterases and two alpha/beta-esterases. On the basis of the inhibition patterns using Malathion and eserine sulfate, 34 bands were classified as carboxylesterases, 14 as acethylesterases and three as cholinesterases. Ten gene loci were tentatively established on the basis of data on band position in the gel, substrate preference and inhibition pattern. Twenty bands were species-specific, the remaining being shared by species from the same or different subgroups. Bands detected exclusively in males and bands with a different frequency or degree of expression between sexes were also detected. In the gels prepared for analysis of gene expression in the body parts (head, thorax and abdomen), the degree of expression of the beta-esterases was higher in the thorax, while the alpha-esterases were expressed predominantly in the abdomen and thorax. A global view of the data available at present on the esterases of the species from the saltans group and their degree of polymorphism are presented, as well as the possibility of using some beta-esterases, because of their characteristics in the gels, as markers for species identification.


Assuntos
Drosophila/enzimologia , Drosophila/genética , Esterases/classificação , Esterases/genética , Variação Genética , Animais , Drosophila/classificação , Esterases/metabolismo , Feminino , Regulação Enzimológica da Expressão Gênica , Marcadores Genéticos , Masculino
12.
J Am Mosq Control Assoc ; 11(3): 363-6, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8551309

RESUMO

Several over-produced esterases confer resistance to organophosphorus insecticides in the Culex pipiens complex. We describe their distribution in islands and countries of the Caribbean region based on new collections and previous studies, and discuss the need to: 1) undertake DNA studies to correctly identify the esterase B alleles that are amplified in different regions, and 2) investigate the variability among gene copies within each amplification system in order to fully understand their origin and their evolution through time.


Assuntos
Culex/enzimologia , Esterases/metabolismo , Animais , Região do Caribe , Esterases/classificação , Serina Endopeptidases/metabolismo , Índias Ocidentais
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