Expanding Actinomycetota Diversity in the TBRC Culture Collection through Metabarcoding and Simulated In Situ Cultivation of Thailand’s Mekong River Microbiota

Abstract

Culture-independent and culture-dependent approaches were employed to investigate the taxonomic diversity and biosynthetic gene cluster potential of Actinomycetota in the Mekong River. Through 16S rRNA gene metabarcoding, 21,103 OTUs were revealed to represent 190 genera and at least 595 species of Actinomycetota, including putatively novel taxa. Conventional and in situ cultivation (IC) methods provided 75 Actinomycetota isolates representing 72 species from 21 genera. Of these, 45 species in 4 genera were new to the Thailand Bioresource Research Center (TBRC), a collection of 20,079 Actinomycetota strains from 660 species. Applying both culture-independent and culture-dependent approaches to the same sample revealed greater diversity among the Actinomycetota in the Mekong River than one approach alone.