RESUMEN
Indonesia's deep-sea microbial communities remain poorly understood, prompting the need for comprehensive investigations. This study aimed to assess the bacterial and archaeal diversities in northwestern Arafura deep-sea sediments, spanning depths of 100 to 1,457 m using a 16S rRNA based-metagenomic sequencing approach, without technical and biological replicates. Principal component analyses based on the Bray-Curtis dissimilarity index indicated that most of the bacterial and archaeal communities were habitat-specific and influenced by depth. The most prevalent known bacterial phylotypes were detected from all samples belonging to the phylum of Desulfobacteriota, Pseudomonadota, and Firmicutes. In addition, the samples also harbored diverse members of the Archaea domain, including Crenarchaeota, Nanoarchaeota and Haloarchaeota. Notably, the sequencing data revealed the significant presence of rare prokaryotic taxa, including uncultured counterparts with less than 1% abundance. The findings suggest that novel and rare prokaryotic taxa are abundant in northwestern Arafura deep-sea ecosystem, offering unique opportunities for further bioprospecting and functional ecology studies.
Asunto(s)
Microbiota , Células Procariotas , Indonesia , ARN Ribosómico 16S/genética , Archaea/genéticaRESUMEN
A polyphasic study was designed to determine the taxonomic status of isolate CSLK01-03T, which was recovered from an Indonesian neutral hot spring and provisionally assigned to the genus Rhodococcus. The isolate was found to have chemotaxonomic, cultural and morphological properties typical of rhodococci. It has a rod-coccus lifecycle and grows from 10 to 39â°C, from pH 6.5 to 8.0 and in the presence of 0-10â% (w/v) sodium chloride. Whole-organism hydrolysates contain meso-diaminopimelic acid, arabinose and galactose, the predominant menaquinone is MK-8 (H2), the polar lipid pattern consists of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol mannosides, phosphatidylmethylethanolamine and two unidentified components, it produces mycolic acids, and C16:0 is the major fatty acid. Whole-genome analyses show that the isolate and Rhodococcus electrodiphilus LMG 29881T (GenBank accession: JAULCK000000000) have genome sizes of 5.5 and 5.1 Mbp, respectively. These strains and Rhodococcus aetherivorans DSM 44752T and Rhodococcus ruber DSM 43338T form well-supported lineages in 16S rRNA and whole-genome trees that are close to sister lineages composed of the type strains of Rhodococcus rhodochrous and related Rhodococcus species. The isolate can be distinguished from its closest evolutionary neighbours using combinations of cultural and phenotypic features, and by low DNA-DNA hybridization values. Based on these data it is proposed that isolate CSLK01-03T (=CCMM B1310T=ICEBB-06T=NCIMB 15214T) be classified in the genus Rhodococcus as Rhodococcus indonesiensis sp. nov. The genomes of the isolate and its closest phylogenomic relatives are rich in biosynthetic gene clusters with the potential to synthesize new natural products, notably antibiotics. In addition, whole-genome-based taxonomy revealed that Rhodococcus electrodiphilus LMG 29881T and Rhodococcus ruber DSM 43338T belong to a single species. It is, therefore, proposed that R. electrodiphilus be recognized as a heterotypic synonym of R. ruber.
Asunto(s)
Manantiales de Aguas Termales , Rhodococcus , Ácidos Grasos/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Filogenia , Composición de Base , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Análisis de Secuencia de ADNRESUMEN
A polyphasic study was undertaken to establish the position of a Streptomyces strain, isolate PRKS01-65T, recovered from sand dune soil collected at Parangkusumo, Yogyakarta Province, Java, Indonesia. A combination of chemotaxonomic, cultural and morphological properties confirmed its position in the genus of Streptomyces. Comparative 16S rRNA gene sequence analyses showed that the isolate was most closely related to Streptomyces leeuwenhoekii C34T (99.9â% similarity) and loosely associated with the type strains of Streptomyces chiangmaiensis (98.7â% similarity) and Streptomyces glomeratus (98.9â% similarity). Multilocus sequence analyses based on five conserved housekeeping gene alleles confirmed the close relationship between the isolate and S. leeuwenhoekii C34T, although both strains belonged to a well-supported clade that encompassed the type strains of S. glomeratus, Streptomyces griseomycini, Streptomyces griseostramineus, Streptomyces labedae, Streptomyces lomondensis and Streptomyces spinoverrucosus. A comparison of the draft genome sequence generated for the isolate with corresponding whole genome sequences of its closest phylogenomic neighbours showed that it formed a well-separated lineage with S. leeuwenhoekii C34T. These strains can also be distinguished using a combination of phenotypic properties and by average nucleotide identity and digital DNA-DNA hybridization similarities of 94.3 and 56â%, values consistent with their classification in different species. Based on this wealth of data it is proposed that isolate PRKS01-65T (=NCIMB 15211T=CCMM B1302T=ICEBB-03T) be classified as Streptomyces harenosi sp. nov. The genome of the isolate contains several biosynthetic gene clusters with the potential to produce new natural products.