RESUMO
Coxsackievirus A6 (CV-A6) has emerged as the predominant causative agent of hand, foot, and mouth disease (HFMD) in young children. Since the declaration of coronavirus disease 2019 (COVID-19) as a global pandemic, the incidence of infectious diseases, including HFMD, has decreased markedly. When social mitigation was relaxed during the COVID-19 pandemic in 2022, the re-emergence of HFMD was observed in Gwangju, South Korea, and seasonal characteristics of the disease appeared to have changed. To investigate the molecular characteristics of enterovirus (EV) associated with HFMD during 2022, 277 specimens were collected. Children aged younger than 5 years accounted for the majority of affected individuals. EV detection and genotyping were performed using real-time RT-PCR and nested RT-PCR followed by sequence analysis. The EV detection rate was found to be 82.3%, and the main genotype identified was CV-A6. Sixteen CV-A6 samples were selected for whole genome sequencing. According to phylogenetic analysis, all CV-A6 strains from this study belonged to the sub-genotype D3 clade based on VP1 sequences. Analysis of 3D polymerase phylogeny showed that only the recombinant RF-A group was identified. In conclusion, circulating EV types should be continuously monitored to understand pathogen emergence and evolution during the post-pandemic era.
Assuntos
Enterovirus , Doença de Mão, Pé e Boca , Criança , Humanos , Pré-Escolar , Doença de Mão, Pé e Boca/epidemiologia , Filogenia , Pandemias , Enterovirus/genética , Antígenos Virais/genética , Reação em Cadeia da Polimerase em Tempo Real , Genótipo , China/epidemiologiaRESUMO
To develop a strain of Saccharomyces cerevisiae that produces ethanol directly from starch, two integrative vectors were constructed to allow the simultaneous multiple integration of the Aspergillus awamori glucoamylase gene (GA1) and the Debaryomyces occidentalis alpha-amylase gene (AMY) and glucoamylase with debranching activity gene (GAM1) into the chromosomes of an industrial strain of S. cerevisiae. The GA1 and AMY genes were constitutively expressed under the ADC1 promoter in S. cerevisiae using the double delta-integration system. The GAM1 gene was constitutively expressed under the corresponding promoter using the double 18S rDNA-integration system. The recombinant industrial strain secreting biologically active alpha-amylase, glucoamylase and debranching enzyme was able to ferment starch to ethanol in a single step. The new strain produced 8% (v/v) ethanol (62.8 g l(-1)) from 20% (w/v) soluble starch after 2 days, fermentation.
Assuntos
Etanol/metabolismo , Engenharia Genética , Glucana 1,4-alfa-Glucosidase/metabolismo , Sistema da Enzima Desramificadora do Glicogênio/metabolismo , Saccharomyces cerevisiae/metabolismo , Amido/metabolismo , alfa-Amilases/metabolismo , Aspergillus/enzimologia , Aspergillus/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Expressão Gênica , Vetores Genéticos , Glucana 1,4-alfa-Glucosidase/genética , Sistema da Enzima Desramificadora do Glicogênio/genética , Recombinação Genética , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Saccharomycetales/enzimologia , Saccharomycetales/genética , alfa-Amilases/genéticaRESUMO
Phytase liberates inorganic phosphate from phytic acid (myo-inositol hexakisphosphate) which is the major phosphate reserve in plant-derived foods and feeds. An industrial strain of Saccharomyces cerevisiae expressing the Debaryomyces castellii phytase gene (phytDc) and D. occidentalis alpha-amylase gene (AMY) was developed. The phytDc and AMY genes were constitutively expressed under the ADC1 promoter in S. cerevisiae by using the delta-integration system, which contains DNA derived exclusively from yeast. The recombinant industrial strain secreted both phytase and alpha-amylase for the efficient degradation of phytic acid and starch as main components of plant seeds. This new strain hydrolyzed 90% of 0.5% (w/v) sodium phytate within 5 days of growth and utilized 100% of 2% (w/v) starch within 48 h simultaneously.
Assuntos
6-Fitase/metabolismo , Ácido Fítico/metabolismo , Saccharomyces cerevisiae/enzimologia , Amido/metabolismo , alfa-Amilases/metabolismo , 6-Fitase/genética , Ração Animal , Animais , Genes Fúngicos , Humanos , Hidrólise , Reação em Cadeia da Polimerase , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Sementes , Transformação Genética , alfa-Amilases/genéticaRESUMO
Amylolytic industrial polyploid strains of Saccharomyces cerevisiae (ATCC 4126, ATCC 9763 and ATCC 24858) expressing a glucoamylase gene (GAM1) or an alpha-amylase gene (AMY) from Debaryomyces occidentalis were developed. The glucoamylase activity of S. cerevisiae ATCC 9763 expressing the GAM1 gene was 3.7-times higher than that of D. occidentalis. On the other hand, alpha-amylase activity in the corresponding strain expressing the D. occidentalis AMY gene increased 10-times relative to D. occidentalis. These two recombinant yeast strains expressing the GAM1 gene and AMY gene, respectively were cultured simultaneously to produce both glucoamylase and alpha-amylase for efficient one-step utilization of starch. Growth, substrate utilization and enzyme activity of these strains are described.