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Dimethylsulfoniopropionate (DMSP) is an abundant organosulfur molecule in the ocean and is the precursor for the climate-active volatile gas dimethyl sulfide. Previous studies focused mainly on bacterial DMSP cycling in seawater, coastal sediment, and surface trench sediment samples, but DMSP metabolism in the Mariana Trench (MT) subseafloor sediments remains unknown.

Site F is the most vigorous cold seep known on the continental slope of the northern South China Sea. Up to now, the microbial community structures in sediments of Site F based on the high-throughput sequencing of the 16S rRNA genes have been studied extensively. However, few studies investigated the microbial community structures at fine vertical scales of Site F and control stations outside Site F. In this study, a comprehensive investigation of microbial communities in sediments of Site F along the depths varying from 0 to 24 cm below sea floor (cmbsf) of four sampling sites—SRS (Southern Reduced Sediment), NRS (Northern Reduced Sediment), Control 1 (close to Site F), and Control 2 (far from Site F)—was carried out. The high relative abundances of anaerobic methanotrophic archaea (ANME), Desulfobacterota [sulfate-reducing bacteria (SRB)], and Campylobacteria [sulfur-oxidizing bacteria (SOB)] in SRS and NRS indicated that these two sites were newborn cold seep sites compared with non-seep sites, Control 1, and Control 2. A positive correlation between ANME-1b, ANME-2, and SEEP-SRB and an enrichment of Sulfurovum and Methlomonadaceae were found in the surface sediments of both SRS and NRS, indicating that the processes of anaerobic oxidation of methane (AOM), sulfur oxidation, and sulfate reduction might occur in seep sites. SRS was enriched with ANME-1b and SEEP-SRB2 with a proposed sulfate-methane transition zone (SMTZ) approximately located at 8 cmbsf. The high abundance of ANME in SRS may due to the high concentration of methane. NRS was enriched with ANME-2, Desulfatiglans, Sulfurovum, and Methanosarcinaceae with a proposed SMTZ at about 10 cmbsf. According to the analyses of microbial community structure and environmental factors, NRS could be described as a notable cold seep reduced sediment site with low sulfate and high H2S that nourished abundant SEEP-SRB1, ANME-2, Methanosarcinales, and Sulfurovum, which showed similar distribution pattern. Our study expands the current knowledge on the differences of microbial communities in cold seep sites and non-seep sites and sheds light on the horizontal and vertical heterogeneity of sediment microbial community in Site F.

A Gram–straining–negative, facultatively anaerobic, motile by means of a polar flagellum and rod-shaped marine bacterium, designated S4M6T, was isolated from surface seawater collected in Dongshan Bay (Fujian, PR China). Phylogenetic analysis based on 16S rRNA genes, phylogenomic analysis of single-copy gene families and whole genome data indicated that S4M6T represented a member of the genus Vibrio . The closest phylogenetic relatives of S4M6T were Vibrio marisflavi CGMCC 1.8994T (97.8 % 16S rRNA gene sequence pairwise similarity), Vibrio variabilis LMG 25438T (96.9 %), Vibrio gangliei SZDIS-1T (96.2 %) and Vibrio aestivus M22T (96.1 %). The growth of S4M6T occurred at 15–35 °C (optimum 28 °C), pH 4.0–9.0 (optimum 5.0–7.0) and in the presence of 2–5 % (w/v) NaCl (optimum 3 %). The predominant fatty acids (>10 %) are C16 : 0, summed feature 3 (C16 : 1ω7c and/or C16 :  1ω6c) and summed feature 8 (C18 : 1ω7c and/or C18 :  1ω6c). The DNA G+C content of the assembled genomic sequences was 43.4 % for S4M6T. Average nucleotide identity (ANI) values between S4M6T and the reference species were lower than the threshold for species delineation (95–96 %); in silico DNA–DNA hybridization further indicated that S4M6T had less than 70 % similarity to its relatives. On the basis of the polyphasic evidence, strain S4M6T is proposed to represent a novel species of the genus Vibrio , for which the name Vibrio sinus sp. nov. is proposed. The type strain is S4M6T (= KCTC 92312T= MCCC 1K06167T).

BackgroundRising incidence of inflammation-related diseases is an increasing concern nowadays. However, while menthol is a wildly-used and efficacious complementary medicine, its pharmacological mechanism still remains uncertain. Superimposed upon that, the aim of this review is to summarize the contemporary evidence of menthol’s anti-inflammatory activity.MethodsUsing the pharmacopeias and electronic databases, including Web of Science, PubMed, and CNKI, this study analyzed the relevant research articles and review articles from 2002 to 2022 and concluded those results and conjectures to finish this article.ResultsThe decrease in pro-inflammatory cytokines and related inflammatory markers, as well as associated pathway activation, was found to play the greatest role in the protective effects of menthol against inflammatory damage or association with protection against chronic inflammation.ConclusionThis review mainly concludes the progress in menthol’s anti-inflammatory activity. Further studies are needed to establish relationships between the mechanisms of action and to clarify the clinical relevance of any anti-inflammatory effects.