Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
1.
Chinese Journal of Biotechnology ; (12): 4550-4562, 2023.
Artículo en Chino | WPRIM | ID: wpr-1008041

RESUMEN

Mycobacterium neoaurum has the ability to produce steroidal intermediates known as 22-hydroxy-23, 24-bisnorchol-4-en-3-one (BA) upon the knockout of the genes for either the hydroxyacyl-CoA dehydrogenase (Hsd4A) or acyl-CoA thiolase (FadA5). In a previous study, we discovered a novel metabolite in the fermentation products when the fadA5 gene was deleted. This research aims to elucidate the metabolic pathway of this metabolite through structural identification, homologous sequence analysis of the fadA5 gene, phylogenetic tree analysis of M. neoaurum HGMS2, and gene knockout. Our findings revealed that the metabolite is a C23 metabolic intermediate, named 24-norchol-4-ene-3, 22-dione (designated as 3-OPD). It is formed when a thioesterase (TE) catalyzes the formation of a β-ketonic acid by removing CoA from the side chain of 3, 22-dioxo-25, 26-bisnorchol-4-ene-24-oyl CoA (22-O-BNC-CoA), followed by spontaneously undergoing decarboxylation. These results have the potential to contribute to the development of novel steroid intermediates.


Asunto(s)
Mycobacterium/metabolismo , Filogenia , Esteroides/metabolismo , Redes y Vías Metabólicas , Esteroles/metabolismo
2.
Electron. j. biotechnol ; 19(6): 84-90, Nov. 2016. ilus
Artículo en Inglés | LILACS | ID: biblio-840318

RESUMEN

Background: 3-Ketosteroid-∆¹-dehydrogenase (KSDD), a flavoprotein enzyme, catalyzes the bioconversion of 4-androstene-3,17-dione (AD) to androst-1,4-diene-3,17-dione (ADD). To date, there has been no report about characterization of KSDD from Mycobacterium neoaurum strains, which were usually employed to produce AD or ADD by fermentation. Results: In this work, Corynebacterium crenatum was chosen asa new host for heterologous expression of KSDD from M. neoaurum JC-12 after codon optimization of the KSDD gene. SDS-PAGE and western blotting results indicated that the recombinant C. crenatum harboring the optimized ksdd (ksdd n) gene showed significantly improved ability to express KSDD. The expression level of KSDD was about 1.6-fold increased C. crenatum after codon optimization. After purification of the protein, we first characterized KSDD from M. neoaurum JC-12, and the results showed that the optimum temperature and pH for KSDD activity were 30°C and pH 7.0, respectively. The Km and Vmax values of purified KSDD were 8.91 µM and 6.43 mM/min. In this work, C. crenatum as a novel whole-cell catalyst was also employed and validated for bioconversion of AD to ADD. The highest transformation rate of AD to ADD by recombinant C. crenatum was about 83.87% after 10 h reaction time, which was more efficient than M. neoaurum JC-12 (only 3.56% at 10 h). Conclusions: In this work, basing on the codon optimization, overexpression, purification and characterization of KSDD, we constructed a novel system, the recombinant C. crenatum SYPA 5-5 expressing KSDD, to accumulate ADDfromADefficiently. This work provided new insights into strengthening sterol catabolism by overexpressing the key enzyme KSDD, for efficient ADD production.


Asunto(s)
Androstadienos/metabolismo , Corynebacterium/enzimología , Mycobacterium/enzimología , Oxidorreductasas/metabolismo , Codón , Proteínas Recombinantes
3.
Braz. j. infect. dis ; 18(2): 235-237, Mar-Apr/2014. graf
Artículo en Inglés | LILACS | ID: lil-709421

RESUMEN

Mycobacterium neoaurum is a rare cause of bacteremia, and infection usually occurs in an immunocompromised host in the setting of an indwelling catheter. Prosthetic valve endocarditis due to non-tuberculous mycobacteria typically carries a dismal prognosis; we report a case ofM. neoaurum prosthetic valve endocarditis with favorable response to antimicrobial therapy without surgical intervention.


Asunto(s)
Adulto , Humanos , Masculino , Endocarditis Bacteriana/microbiología , Prótesis Valvulares Cardíacas/microbiología , Infecciones por Mycobacterium/microbiología , Mycobacterium/aislamiento & purificación , Infecciones Relacionadas con Prótesis/microbiología , Endocarditis Bacteriana/diagnóstico , Infecciones por Mycobacterium/diagnóstico , Mycobacterium/clasificación , Infecciones Relacionadas con Prótesis/diagnóstico
4.
Annals of Laboratory Medicine ; : 243-246, 2014.
Artículo en Inglés | WPRIM | ID: wpr-163726

RESUMEN

Mycobacterium neoaurum is rapidly growing mycobacteria that can cause human infections. It commonly causes bloodstream infections in immunocompromised hosts, and unlike other mycobacteria species, it rarely causes pulmonary infections. We confirmed the first pulmonary infection case in Korea caused by M. neoaurum using full-length 16S rRNA gene sequencing.


Asunto(s)
Adulto , Femenino , Humanos , Enfermedades Pulmonares/diagnóstico , Mycobacterium/genética , Infecciones por Mycobacterium/diagnóstico , Micobacterias no Tuberculosas/genética , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ARN
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA