title: Diversity of culturable actinobacteria isolated from marine sponge Haliclona sp.
abstract: This study describes actinobacteria isolated from the marine sponge Haliclona sp. collected in shallow water of the South China Sea. A total of 54 actinobacteria were isolated using media selective for actinobacteria. Species diversity and natural product diversity of isolates from marine sponge Haliclona sp. were analysed. Twenty-four isolates were selected on the basis of their morphology on different media and assigned to the phylum Actinobacteria by a combination of 16S rRNA gene based restriction enzymes digestion and 16S rRNA gene sequence analysis. The 16S rRNA genes of 24 isolates were digested by restriction enzymes TaqI and MspI and assigned to different groups according to their restriction enzyme pattern. The phylogenetic analysis based on 16S rRNA gene sequencing showed that the isolates belonged to the genera Streptomyces, Nocardiopsis, Micromonospora and Verrucosispora; one other isolate was recovered that does not belong to known genera based on its unique 16S rRNA gene sequence. To our knowledge, this is the first report of a bacterium classified as Verrucosispora sp. that has been isolated from a marine sponge. The majority of the strains tested belong to the genus Streptomyces and three isolates may be new species. All of the 24 isolates were screened for genes encoding polyketide synthases (PKS) and nonribosomal peptide synthetases (NRPS). PKS and NRPS sequences were detected in more than half of the isolates and the different "PKS-I-PKS-II-NRPS" combinations in different isolates belonging to the same species are indicators of their potential natural product diversity and divergent genetic evolution.
authors.affiliation: Key Laboratory of Marine Bio-resources Sustainable Utilization (LMB-CAS), Guangdong Key Laboratory of Marine Materia Medica (LMMM-GD), South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China.
authors.forename: Shumei
authors.initials: S
authors.lastname: Jiang
authors.forename: Wei
authors.initials: W
authors.lastname: Sun
authors.forename: Minjie
authors.initials: M
authors.lastname: Chen
authors.forename: Shikun
authors.initials: S
authors.lastname: Dai
authors.forename: Long
authors.initials: L
authors.lastname: Zhang
authors.forename: Yonghong
authors.initials: Y
authors.lastname: Liu
authors.forename: Kyung Jin
authors.initials: KJ
authors.lastname: Lee
authors.forename: Xiang
authors.initials: X
authors.lastname: Li
mesh_terms: D039903:Actinobacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics; D044822:Biodiversity; D002681:China; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D019003:Deoxyribonuclease HpaII / Q000378:metabolism; D015252:Deoxyribonucleases, Type II Site-Specific / Q000378:metabolism; D020459:Genes, rRNA; D047129:Haliclona / Q000382:microbiology*; D008969:Molecular Sequence Data; D010453:Peptide Synthases / Q000235:genetics; D010802:Phylogeny; D048630:Polyketide Synthases / Q000235:genetics; D012150:Polymorphism, Restriction Fragment Length; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D048630:Polyketide Synthases; D019003:Deoxyribonuclease HpaII; D015252:Deoxyribonucleases, Type II Site-Specific; C027046:TCGA-specific type II deoxyribonucleases; D010453:Peptide Synthases; C104385:non-ribosomal peptide synthase