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1.
Braz. j. biol ; 83: e243629, 2023. tab, graf
Artigo em Inglês | LILACS-Express | MEDLINE, LILACSEXPRESS | ID: biblio-1285611

RESUMO

Abstract As an important enzyme, xylanase is widely used in the food, pulp, and textile industry. Different applications of xylanase warrant specific conditions including temperature and pH. This study aimed to carry out sodium alginate beads as carrier to immobilize previous reported mutated xylanase from Neocallimastix patriciarum which expressed in E. coli, the activity of immobilization of mutated xylanase was elevated about 4% at pH 6 and 13% at 62 °C. Moreover, the immobilized mutated xylanase retained a greater proportion of its activity than the wide type in thermostability. These properties suggested that the immobilization of mutated xylanase has potential to apply in biobleaching industry.


Resumo Como importante enzima, a xilanase é amplamente utilizada na indústria alimentícia, de celulose e têxtil. Diferentes aplicações de xilanase garantem condições específicas, incluindo temperatura e pH. Este estudo teve como objetivo realizar grânulos de alginato de sódio como carreador para imobilizar xilanase mutada relatada anteriormente de Neocallimastix patriciarum que expressa em E. coli, a atividade de imobilização da xilanase mutada foi elevada em cerca de 4% em pH 6 e 13% a 62 °C. Além disso, a xilanase mutada imobilizada reteve uma proporção maior de sua atividade do que o tipo amplo em termoestabilidade. Essas propriedades sugerem que a imobilização da xilanase mutada tem potencial para aplicação na indústria de biobranqueamento.

2.
Braz J Biol ; 83: e243629, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34378657

RESUMO

As an important enzyme, xylanase is widely used in the food, pulp, and textile industry. Different applications of xylanase warrant specific conditions including temperature and pH. This study aimed to carry out sodium alginate beads as carrier to immobilize previous reported mutated xylanase from Neocallimastix patriciarum which expressed in E. coli, the activity of immobilization of mutated xylanase was elevated about 4% at pH 6 and 13% at 62 °C. Moreover, the immobilized mutated xylanase retained a greater proportion of its activity than the wide type in thermostability. These properties suggested that the immobilization of mutated xylanase has potential to apply in biobleaching industry.


Assuntos
Neocallimastix , Escherichia coli/genética , Temperatura
5.
Hum Immunol ; 77(5): 411-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26972750

RESUMO

Previous studies indicate the distribution of major histocompatibility complex class I chain-related genes A (MICA) and B (MICB) alleles and haplotypes varies widely between different ethnic populations and geographic areas. It is meaningful to investigate allelic frequencies and establish a genetic database. In this study, we firstly reported the polymorphic variation of MICA/B in 187 healthy, unrelated Tujia individuals in Zhangjiajie region, China. Using polymerase chain reaction-sequence specific priming (PCR-SSP) and sequencing-based typing (PCR-SBT), we identified eight MICA-sequence alleles, four MICA-short tandem repeat variants, and 13 MICB variants, of which MICA(∗)008:04 (29.41%), MICA(∗)A5 (29.68%), MICA(∗)A5.1 (29.68%) and MICB(∗)005:02 (39.57%) were the most frequent. Linkage disequilibrium analysis further revealed MICB(∗)005:02-MICA(∗)019 (13.10%) and MICB(∗)002-MICA(∗)008:04 (9.89%) as the most common two-locus haplotypes. Data comparison by neighbor-joining dendrograms and principal component analysis to verify allelic frequencies in other Chinese and Asia ethnic groups showed that the Zhangjiajie Tujias were genetically closer to the Guangdong Han population, based on MICA loci variability. Our results provide new information about the MICA/B gene polymorphism in Chinese Tujia population, which will form the basis for future studies on the potential role of MICA/B in allogeneic organ transplantation and disease susceptibility in related ethnic groups.


Assuntos
Grupos Étnicos , Antígenos de Histocompatibilidade Classe I/genética , Repetições de Microssatélites/genética , Adulto , China , Feminino , Frequência do Gene , Predisposição Genética para Doença , Haplótipos , Humanos , Desequilíbrio de Ligação/genética , Masculino , Transplante de Órgãos , Reação em Cadeia da Polimerase , Polimorfismo Genético , Análise de Componente Principal
6.
Hum Immunol ; 77(4): 340-1, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26826451

RESUMO

One hundred eighty-seven Tujia individuals from Zhangjiajie, Hunan Province, China were genotyped at the MICA and MICB loci using polymerase chain reaction-sequence specific priming and sequencing-based typing methods. MICA and MCB genotypes are consistent with expected HW proportions. These genotype data are available in the Allele Frequencies Net Database.


Assuntos
Grupos Étnicos/genética , Genótipo , Antígenos de Histocompatibilidade Classe I/genética , China , Frequência do Gene , Humanos , Polimorfismo Genético
7.
Yao Xue Xue Bao ; 26(6): 451-7, 1991.
Artigo em Chinês | MEDLINE | ID: mdl-1789113

RESUMO

This paper provides the basic principle and experimental technique of differential--linear combination equal value derivative spectrophotometry. Quantitative analysis of three or four component--mixture can be done without separation. This method was investigated to assay the contents of chlorphenamine and propantheline bromide in Pukeling tablets by using UV-210A spectrophotometer. The average recoveries of chlorphenamine and propantheline bromide were 100.2 +/- 1.49% (CV) and 99.89 +/- 1.03% (CV) respectively. The results showed that it not only can effectively remove disturbances from each other, but also give higher sensitivity and accuracy.


Assuntos
Clorfeniramina/análise , Propantelina/análise , Combinação de Medicamentos , Espectrofotometria Ultravioleta/métodos , Comprimidos/análise
8.
Hemoglobin ; 12(5-6): 691-7, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3209411

RESUMO

A new method for labeling oligonucleotides was developed to obtain high specific activity of radioactive probes. In an oligonucleotide molecule, two sequences were designed. One sequence, the 5', contains 19 nucleotides and serves as a template for probe synthesis. The second sequence, 3', contains a consensus sequence which forms a Pst I site after forming a complementary strand with the primer. In the presence of E. coli DNA polymerase I (Klenow fragment), alpha-32P dNTP and other dNTPs, a radioactive labeled oligonucleotide was synthesized by the primer extension method. After Pst I digestion, the probe was different from its template in length by 4 bp and could be separated from each other on urea-polyacrylamide gel electrophoresis (PAGE). A radioactive oligonucleotide probe with extremely high specific activity up to 10(10) dpm/micrograms could be obtained by the use of this method. The oligonucleotide probes have been used for the detection of the Hb E mutation in this report.


Assuntos
Hemoglobina E/genética , Hemoglobinas Anormais/genética , Sequência de Bases , DNA/isolamento & purificação , Humanos , Dados de Sequência Molecular , Sondas de Oligonucleotídeos , Oligonucleotídeos/síntese química , Fenótipo , Moldes Genéticos
13.
Prenat Diagn ; 6(2): 89-95, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3010268

RESUMO

By means of chorion biopsy together with restriction endonuclease analysis of fetal DNA, first trimester diagnoses were successfully made in 33 fetuses at risk for Bart's hydrops fetalis. Seven pregnancies with Hb H or hydrops fetalis were therapeutically terminated before 4 1/2 months of gestation. Of the 26 pregnancies intended to continue, 18 have come to term with normal deliveries; one with threatened abortion was terminated at the end of the first trimester and, seven are progressing normally.


Assuntos
Vilosidades Coriônicas/patologia , Diagnóstico Pré-Natal , Talassemia/diagnóstico , Biópsia , Mapeamento Cromossômico , Enzimas de Restrição do DNA , Edema/diagnóstico , Feminino , Genótipo , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Trofoblastos/patologia
19.
Hum Genet ; 71(3): 225-6, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3877675

RESUMO

The frequencies of alpha-1-antitrypsin alleles were determined for five Chinese national minorities: Uigur, Korean, Mongolian, Chuang, and Li. PI S and PI Z alleles are not found in the five populations studied. PI ETOK allele is present in Korean, Mongolian, and Chuang populations, and Etokyo is a very common alpha-1-antitrypsin variant in Chinese. Other alleles which occur in more than one of the minorities are PI X (Mongolian and Chuang) and PI M4 (Korean and Uigur). The high frequency of PI M4 in the Uigur population suggests a probably Occidental origin of this nationality.


Assuntos
Alelos , alfa 1-Antitripsina/genética , China , Grupos Étnicos , Frequência do Gene , Humanos , Focalização Isoelétrica
20.
Hum Genet ; 69(2): 184-7, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3871725

RESUMO

Alpha-1-antitrypsin phenotypes of six Chinese Han populations (20 degrees-45 degrees N. latitude) were determined. The frequency of allele M2 increases from North to South China. The north-south change of M2 appears to be mainly at the expense of alleles M1 and M3. Geographical variability of other variants was also observed. In the northern populations, the most common variants are M4 and Etokyo; in the southern populations, Pweishi, a variant which can not be distinguished electrophoretically from Pyasugi. These results form a distribution pattern of alpha-1-antitrypsin alleles in China.


Assuntos
Alelos , Frequência do Gene , alfa 1-Antitripsina/genética , China , Feminino , Genética Populacional , Humanos , Focalização Isoelétrica , Masculino , Linhagem , Fenótipo
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