ABSTRACT
Actinobacteria comprise diverse groups of bacteria capable of full degradation, or modification of different steroid compounds. Steroid catabolism has been characterized best for the representatives of suborder Corynebacterineae, such as Mycobacteria, Rhodococcus and Gordonia, with high content of mycolic acids in the cell envelope, while it is poorly understood for other steroid-transforming actinobacteria, such as representatives of Nocardioides genus belonging to suborder Propionibacterineae. Nocardioides simplex VKM Ac-2033D is an important biotechnological strain which is known for its ability to introduce ∆(1)-double bond in various 1(2)-saturated 3-ketosteroids, and perform convertion of 3ß-hydroxy-5-ene steroids to 3-oxo-4-ene steroids, hydrolysis of acetylated steroids, reduction of carbonyl groups at C-17 and C-20 of androstanes and pregnanes, respectively. The strain is also capable of utilizing cholesterol and phytosterol as carbon and energy sources. In this study, a comprehensive bioinformatics genome-wide screening was carried out to predict genes related to steroid metabolism in this organism, their clustering and possible regulation. The predicted operon structure and number of candidate gene copies paralogs have been estimated. Binding sites of steroid catabolism regulators KstR and KstR2 specified for N. simplex VKM Ac-2033D have been calculated de novo. Most of the candidate genes grouped within three main clusters, one of the predicted clusters having no analogs in other actinobacteria studied so far. The results offer a base for further functional studies, expand the understanding of steroid catabolism by actinobacteria, and will contribute to modifying of metabolic pathways in order to generate effective biocatalysts capable of producing valuable bioactive steroids.
Subject(s)
Actinobacteria/genetics , Actinobacteria/metabolism , Computational Biology , Gene Expression Regulation, Bacterial , Genes, Bacterial , Genome-Wide Association Study , Steroids/metabolism , Amino Acid Motifs , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Computational Biology/methods , Databases, Genetic , Gene Expression Regulation, Enzymologic , Gene Ontology , Genome, Bacterial , Genome-Wide Association Study/methods , Genomics , Metabolic Networks and Pathways , Molecular Sequence Annotation , Multigene Family , Position-Specific Scoring Matrices , Protein Interaction Domains and MotifsABSTRACT
Nocardioides simplex VKM Ac-2033D is an effective microbial catalyst for 3-ketosteroid 1(2)-dehydrogenation, and it is capable of effective reduction of carbonyl groups at C-17 and C-20, hydrolysis of acetylated steroids, and utilization of natural sterols. Here, the complete genome sequence is reported. An array of genes related to steroid metabolic pathways have been identified.
ABSTRACT
Mycobacterium sp. strain VKM Ac-1817D is capable of converting phytosterol into 9α-hydroxy androst-4-ene-3,17-dione (9-OH-AD), which is a valuable intermediate for the steroid pharmaceutical industry. Here, a complete genome sequence of the strain is reported. The genome consists of a single circular 6,324,222-bp chromosome with a G+C content of 66.2% and encodes approximately 6,000 CDSs, 54 tRNAs, and 6 rRNAs.
ABSTRACT
Mycobacterium neoaurum strain VKM Ac-1815D produces 4-androstene-3,17-dione as a major compound from phytosterols. Here, we report the complete genome sequence of the strain. The genome consists of a single circular 5,438,190-bp chromosome, with a G+C content of 66.88%, containing 5,318 putative open reading frames (ORFs), 46 tRNAs, and 6 rRNAs. Arrays of cholesterol metabolism genes are randomly clustered throughout the chromosome.
