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A novel endophytic actinomycete, strain MEP2-6T, was isolated from scab tissues of potato tubers collected from Mae Fag Mai Sub-district, San Sai District, Chiang Mai Province, Thailand. Strain MEP2-6T is a gram-positive filamentous bacteria characterized by meso-diaminopimelic acid in cell wall peptidoglycan and arabinose, galactose, glucose, and ribose in whole-cell hydrolysates. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, and hydroxy-phosphatidylethanolamine were the major phospholipids, of which MK-9(H6) was the predominant menaquinone, whereas iso-C16:0 and iso-C15:0 were the major cellular fatty acids. The genome of the strain was 10,277,369 bp in size with a G + C content of 71.7%. The 16S rRNA gene phylogenetic and core phylogenomic analyses revealed that strain MEP2-6T was closely related to Amycolatopsis lexingtonensis NRRL B-24131T (99.4%), A. pretoriensis DSM 44654T (99.3%), and A. eburnea GLM-1T (98.9%). Notably, strain MEP2-6T displayed 91.7%, 91.8%, and 87% ANIb and 49%, 48.8%, and 35.4% dDDH to A. lexingtonensis DSM 44653T (=NRRL B-24131T), A. eburnea GLM-1T, and A. pretoriensis DSM 44654T, respectively. Based on phenotypic, chemotaxonomic, and genomic data, strain MEP2-6T could be officially assigned to a novel species within the genus Amycolatopsis, for which the name Amycolatopsis solani sp. nov. has been proposed. The type of strain is MEP2-6T (=JCM 36309T = TBRC 17632T = NBRC 116395T). Amycolatopsis solani MEP2-6T was strongly proven to be a non-phytopathogen of potato scab disease because stunting of seedlings and necrotic lesions on potato tuber slices were not observed, and there were no core biosynthetic genes associated with the BGCs of phytotoxin-inducing scab lesions. Furthermore, comparative genomics can provide a better understanding of the genetic mechanisms that enable A. solani MEP2-6T to adapt to the plant endosphere. Importantly, the strain smBGCs accommodated 33 smBGCs encoded for several bioactive compounds, which could be beneficially applied in the fields of agriculture and medicine. Consequently, strain MEP2-6T is a promising candidate as a novel biocontrol agent and antibiotic producer. [ABSTRACT FROM AUTHOR]

Twelve tetracocci isolated from Thai fermented fish products (pla-ra, kung-chom and nam-pla) were screened for their lipolytic activity on agar plates. Most of them exhibited lipolytic activity on the medium supplemented with 1% (v/v) of tributyrin, Tween 20, Tween 40, Tween 60 or Tween 80. The isolates exhibited lipolytic activity ranging from 0.042±0.032 to 9.548±0.969 Units•mL-1 and from 0.111±0.023 to 5.939±0.119 Units•mL-1 when cultivated in broth supplemented with 1% (v/v) Tween 20 and Tween 80, respectively. In the media containing 1% (v/v) coconut oil, lard or palm oil, the lypolytic activity was 0.042±0.032 to 9.548±0.969 Units•mL-1, 0.548±0.009 to 6.00±0.136 Units•mL-1 and 0.83 ±0.020 to 5.25±0.030 Units•mL-1, respectively, when incubated at 37° Cfor 24 h. The isolates were identified as members of the genus Staphylococcus based on their phenotypic characteristics and 16S rRNA gene sequences. They were closely related to S. nepalensis NCTC 13834T, S. condimenti DSM 11674T, S. simulans ATCC 27848T, S. hominis subsp. novobiosepticus GTC 1228T, S. edaphicus P5085T, S. saprophyticus subsp. saprophyticus ATCC 15305T and S. lloydii ATCC 43959T, with 99.78-100 % similarity. Isolate SPJ-1 from kung-chom, identified as S. condimenti, exhibited the highest lipolytic activity (6.287±0.159, 5.939±0.119 and 5.996±0.136 Units•mL-1) when cultivated in Tween 20, Tween 80 and lard. [ABSTRACT FROM AUTHOR]