Chitti Thawai

Micromonospora spongicola sp. nov., an actinomycete isolated from a marine sponge in the Gulf of Thailand

An actinomycete strain, S3-1T, was isolated from marine sponge sample collected from the Gulf of Thailand. The strain is aerobic, Gram-positive and produced single spores at the tip of the substrate mycelium. Strain S3-1T contained meso-diaminopimelic acid in the peptidoglycan, whole-cell sugars were arabinose, galactose, glucose, rhamnose, ribose and xylose. The polar lipid profile of strain S3-1T consisted of phosphatidylethanolamine, phosphatidylmethylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannosides, phosphoglycolipid and unknown polar lipids. Morphological and chemotaxonomic characteristics of the strain were identified as a member of the genus Micromonospora. Phylogenetic analysis based on 16S rRNA gene sequence analysis of the strain showed similarity to Micromonospora nigra DSM 43818T (98.8%), Micromonospora yangpuensis FXJ6.011T (98.7%) and Micromonospora narathiwatensis BTG4-1T (98.6%). The DNA G+C content was 72.7 mol%. The phenotypic characteristics and DNA–DNA relatedness values supported that the classification of this strain as a novel species in the genus Micromonospora, for which the name Micromonospora spongicola sp. nov. (type strain S3-1T =BCC 45595T=NBRC 108779T) is proposed.

Micromonospora endophytica sp. nov., an endophytic actinobacteria of Thai upland rice ( Oryza sativa )

An actinobacterial strain, DCWR9-8-2T, was isolated from a leaf of Thai upland rice (Oryza sativa) collected in Chumporn province, Thailand. Strain DCWR9-8-2T is Gram-stain-positive aerobic bacteria that produce single spores directly on the vegetative hypha. Cell wall peptidoglycan of this strain exhibits meso-diaminopimelic acid and glycine, the reducing sugars of whole-cell hydrolysate are arabinose, glucose, ribose, xylose and small amount of mannose. The phospholipid profiles in the membrane are comprised of phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannosides. The major menaquinones are MK-9(H4) and MK-10(H6). The diagnostic cellular fatty acids are iso-C16:0 and iso-C15:0. The G+C content of the genomic DNA is 72.5 mol%. The result of 16S rRNA sequence analysis of the strain revealed that this strain was closely related to Micromonospora auratinigra TT1-11T (99.25%). On the other hand, the result of gyrB gene sequence analysis revealed that this strain was closed to M. eburnea JCM 12345T (96.30%). In addition, a combination of DNA–DNA hybridization results and some phenotypic properties supported that this strain should be judged as a novel species of the genus Micromonospora, for which the name M. endophytica sp. nov. is proposed. The type strain is DCWR9-8-2T (=BCC 67267T=NBRC 110008T).

Actinoplanes siamensis sp. nov., isolated from soil.

A Gram-positive filamentous bacterial strain that developed large campanulate sporangia at the ends of sporangiophores on substrate mycelium was isolated from bamboo forest soil in Thailand. According to the results of a polyphasic taxonomic study, our isolate had typical characteristics of members of the genus Actinoplanes. The 16S rRNA gene sequence analysis also indicated that strain A-T 6646(T) belonged to the genus Actinoplanes, being most closely related to Actinoplanes liguriensis DSM 43865(T) (97.61 %) and Actinoplanes octamycinicus NBRC 14524(T) (97.52 %). The DNA-DNA relatedness values, which differentiate the new strain from the most closely related species, were significantly below 70 %. The cell-wall peptidoglycan contained meso-diaminopimelic acid. The whole-cell sugars contained xylose and arabinose. The predominant menaquinone was MK-9(H4). The diagnostic phospholipids were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol. The predominant cellular fatty acids were iso-C16 : 0, anteiso-C17 : 0, iso-C15 : 0 and anteiso-C15 : 0. Following an evaluation of phenotypic, chemotaxonomic and genotypic studies, the isolate is proposed to represent a novel species to be named Actinoplanes siamensis sp. nov. The type strain is A-T 6646(T) (= BCC 46194(T) = NBRC 109076(T)).

Sinosporangium siamense sp. nov., isolated from soil and emended description of the genus Sinosporangium.

An actinomycetes strain A-T 1946(T) that developed spherical sporangia containing non-motile spores on aerial mycelia was isolated from dry deciduous forest soil in Thailand. 16S rRNA gene sequence analysis indicated that strain A-T 1946(T) belongs to the genus Sinosporangium, being closely related to Sinosporangium album 6014(T) (98.8% sequence similarity). The DNA-DNA relatedness values were 43.7-50.9%, which were significantly below 70% and differentiated strain A-T 1946(T) from the closest species. The cell-wall peptidoglycan contained meso-diaminopimelic acid. The whole-cell sugars contained rhamnose, ribose, madurose and glucose. The predominant menaquinone was MK-9(H2). The diagnostic phospholipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, lysophosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol-mannoside, N-acetylglucosamine-containing phospholipids, two unknown phosphoglycolipids and two unknown phospholipids. The predominant cellular fatty acids were unsaturated C(16 : 1) and C(17 : 1), and saturated C(16 : 0) and 10-methyl-C(17 : 0). Following an evaluation of phenotypic, chemotaxonomic and genotypic characteristics, the isolate is proposed to represent a novel species of genus Sinosporangium to be named Sinosporangium siamense sp. nov. The type strain is A-T 1946(T) ( = BCC 29081(T) = NBRC 109515(T)). An emended description of the genus Sinosporangium is also provided.

Sinosporangium fuscum sp. nov., isolated from soil

A novel actinomycete, A-T 8343T was isolated from a moist evergreen forest soil sample collected in the Trat Province, Thailand. Based on 16S rRNA gene sequence analysis, strain A-T 8343T belonged to the genus Sinosporangium and was closely related to Sinosporangium siamense A-T 1946T (98.81 %) and Sinosporangium album 6014T (98.54 %). The DNA-DNA relatedness values were 21.8-27 % with S. siamense A-T 1946T and 31.1-31.9 % with S. album 6014T, which were significantly below 70 %. The result differentiated A-T 8343T from the closest species. The organism developed spherical sporangia containing non-motile spores on aerial mycelia. The cell-wall peptidoglycan contained meso-diaminopimelic acid. The whole-cell sugars contained rhamnose, ribose, madurose and glucose. The predominant menaquinones were MK-9(H2) and MK-9(H4). The diagnostic phospholipids were phosphatidylmethylethanolamine, phosphatidylethanolamine, hydroxyl-phosphatidylethanolamine, diphosphatidylglycerol, lyso-phosphatidylethanolamine, N-acetylglucosamine-containing phospholipids, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol-mannosides, aminophosphoglycolipid and one unknown phospholipid. The major cellular fatty acids were saturated C16 : 0, iso C16 : 0, unsaturated C16 : 1 and C18 : 1. Following an evaluation of phenotypic, chemotaxonomic and genotypic characteristics, the new isolate is proposed as a representative novel species of the genus Sinosporangium to be named Sinosporangiumfuscum sp. nov. The type strain is A-T 8343T ( = BCC 52770T = NBRC 109516T).