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Actinomycetes are outstanding collection of microorganisms with numerous affiliates reported for different kinds of bioactive features and extensive commercial importance.Several reports on the ecology of actinomycetes have described that these microorganisms arewide spread in nature and may occur in extreme environments.In this study,we investigated the actinobacteria community structure in sediments collected from the Zhaoqing,Haizhuand Nansha Wetlands in Guangdong.In total,80 sediments samples were taken from three different wetlands during theperiod from February of 2013 to December of 2014.In our work,three pretreatments and five selective isolation media were used to isolate actinomycetes from the sediments.More than 1200 actinomycete-like colonies were isolated,and according to sample sources,cultural characteristics and morphological features 340 representative isolates were selected for 16S rRNA gene sequencing.The identification based onl6S rRNA gene sequencing revealed a high diversity of the isolates,which were distributed into at least 30 genera(Actinocatenispora,Actinocorallia,Actinomadura,Actinopolymorpha,Amycolatopsis,Catellatospora,Cellulomonas,Dactylosporangium,Gordonia,Isoptericola,Knoellia,Microbacterium,Microbispora,Micrococcus,Micromonospora,Microtetraspora,Mumia,Nocardia,Nonomuraea,Plantactinospora,Rhodococcus,Rugosimonospora,Saccharopolyspora,Saccharothrix,Sphaerisporangium,Streptacidiphilus,Streptomyces,Terracoccus,Verrucosispora & Xylanimicrobium),13families(Actinosynnemataceae,Cellulomonadaceae,Intrasporangiaceae,Microbacteriaceae,Micrococcaceae,Micromonosporaceae,Nocardiaceae,Nocardioidaceae,Promicromonospore,Pseudonocardiaceae,Sterptomycetaceae,Streptosporangiaceae & Thermomonosporaceae)and 7 orders(Corynebacterineae,Micrococcineae,Micromonosporineae,Propionibacterineae,Pseudonocardineae,Streptomycineae & Streptosporangineae)within the class Actinobacteria.Then,to study their associated potential capacity to synthesize diverse bioactive natural products,diversity of genes associated with secondary-metabolite biosynthesis including PKS Ⅰ,PKS Ⅱ,NRPS,CYP,HMGR and AHBA were investigated among the isolates.High frequencies of PCR amplification were obtained for PKS-Ⅰ 21.3%,PKS-Ⅱ 34.3%,NRPS 12.6%,CYP21.5%,HMGR7.3%and AHBA5.9%.These results demonstrate that the sediments collected fromwetlands are rich reservoir for diverse culturable actinomycetes,notably members of the genera Streptomyces and Nocardia with the capacity to synthesis novel bioactive compounds.