Genome-Wide Identification and Biochemical Characterization of Alcohol Acyltransferases for Aroma Generation in Isolates from Fermented Food.

The importance of nonconventional yeasts has increasingly been highlighted, particularly for aroma formation in fermented foods. Here, we performed whole-genome sequencing of , which produces a variety of volatile flavor compounds, leading to the identification of the alcohol acyltransferase (AATase) family of genes. The genome of contains seven AATase genes, encoding alcohol--acetyltransferases (ATFs) and ethanol acetyltransferase 1 (EAT1) for acetate ester formation, along with ethanol hexanoyl transferase 1 (EHT1) for ethyl ester formation.

Elucidation and engineering of Sphingolipid biosynthesis pathway in Yarrowia lipolytica for enhanced production of human-type sphingoid bases and glucosylceramides.

Sphingolipids are vital membrane components in in mammalian cells, plants, and various microbes. We aimed to explore and exploit the sphingolipid biosynthesis pathways in an oleaginous and dimorphic yeast Yarrowia lipolytica by constructing and characterizing mutant strains with specific gene deletions and integrating exogenous genes to enhance the production of long-chain bases (LCBs) and glucosylceramides (GlcCers). To block the fungal/plant-specific phytosphingosine (PHS) pathway, we deleted the SUR2 gene encoding a sphinganine C4-hydroxylase, resulting in a remarkably elevated secretory production of dihydrosphingosine (DHS) and sphingosine (So) without acetylation.

sp. nov. and sp. nov., isolated from marine red algae.

Two Gram-stain-negative, strictly aerobic, non-motile, rod-shaped bacteria, designated as strains S88 and W115, exhibiting catalase- and oxidase-positive reactions, were isolated from marine red algae in South Korea. Strain S88 exhibited growth at 20-30 °C, pH 6.0-9.

sp. nov., isolated from kimchi, a fermented vegetable.

The novel strain CBA3628 was isolated from kimchi, a Korean fermented vegetable. CBA3628 is a cocci-shaped, Gram-stain-positive, catalase- and oxidase-negative and facultatively anaerobic bacterium. The results of phylogenetic analysis based on 16S rRNA gene sequencing indicated that CBA3628 represented a member of the genus of the family .

sp. nov., isolated from seawater, reclassification of as a later heterotypic synonym of , and emended description of Kim . 2013.

A Gram-stain-negative, yellow-pigmented, and strictly aerobic bacterium, designated as strain MSW5, was isolated from seawater of the Yellow Sea in South Korea. The cells were non-motile rods exhibiting oxidase- and catalase-positive activities. Growth was observed at 15-25 °C (optimum, 25 °C) and pH 5.

sp. nov. and sp. nov., and reclassification of , , and as later heterotypic synonyms of , , and .

Two Gram-negative, obligately aerobic, rod-shaped bacteria, strains G1-22 and G1-23, were isolated from the phycosphere of a marine brown alga. Both strains exhibited catalase- and oxidase-positive activities. Strain G1-22 displayed optimal growth at 25 °C, pH 8.

Fermentative metabolic features of doenjang-meju as revealed by genome-centered metatranscriptomics.

Fermentative features of doenjang-meju, a traditional Korean soybean brick, were investigated over 45 days via genome-centered metatranscriptomics. The pH value rapidly decreased within 10 days and successively increased after 20 days, along with an initial bacterial growth, including lactic acid bacteria, and subsequent fungal growth, suggesting their association. Polysaccharides and lipids underwent degradation, and amino acids, free sugars, and organic acids increased during the early stage.

ChatGPT and generative AI are revolutionizing the scientific community: A Janus-faced conundrum.

The advent of generative artificial intelligence (AI) technologies marks a transformative moment for the scientific sphere, unlocking novel avenues to elevate scientific writing's efficiency and quality, expedite insight discovery, and enhance code development processes. Essential to leveraging these advancements is prompt engineering, a method that enhances AI interaction efficiency and quality. Despite its benefits, effective application requires blending researchers' expertise with AI, avoiding overreliance.

Metabolic relationships between marine red algae and algae-associated bacteria.

Unlabelled: Mutualistic interactions between marine phototrophs and associated bacteria are an important strategy for their successful survival in the ocean, but little is known about their metabolic relationships. Here, bacterial communities in the algal sphere (AS) and bulk solution (BS) of nine marine red algal cultures were analyzed, and and were identified significantly more abundantly in AS than in BS. The metabolic features of RMAR6-6 (isolated and genome-sequenced), MAG 12 (obtained by metagenomic sequencing), and a marine red alga, CCMP1328 (from GenBank), were analyzed bioinformatically.

sp. nov. and sp. nov., isolated from marine brown algae.

Two Gram-stain-negative, rod-shaped bacteria, designated as strains KJ10-1 and KJ40-1, were isolated from marine brown algae. Both strains were catalase-positive, oxidase-positive, and facultative aerobic. Strain KJ10-1 exhibited optimal growth at 25 °C, pH 7.

sp. nov., isolated from a marine green alga.

A Gram-stain-negative, facultative aerobic, catalase- and oxidase-positive, non-motile, non-flagellated, and coccus-shaped bacterium, strain J2-16, isolated from a marine green alga, was characterized taxonomically. Strain J2-16 grew at 20-40 °C (optimum, 30 °C), pH 6.0-10.

sp. nov. and sp. nov., isolated from marine algae.

Two Gram-stain-negative, facultatively aerobic, and motile rod bacteria, designated as strains KJ51-3 and 15G1-11, were isolated from marine algae collected in the Republic of Korea. Both strains exhibited catalase- and oxidase-positive activities. Optimum growth conditions for strain KJ51-3 were observed at 30 °C and pH 6.

Sustainable control of Microcystis aeruginosa, a harmful cyanobacterium, using Selaginella tamariscina extracts.

Eco-friendly reagents derived from plants represent a promising strategy to mitigate the occurrence of toxic cyanobacterial blooms. The use of an amentoflavone-containing Selaginella tamariscina extract (STE) markedly decreased the number of Microcystis aeruginosa cells, thus demonstrating significant anti-cyanobacterial activity. In particular, the Microcystis-killing fraction obtained from pulverized S.

Biological and Chemical Approaches for Controlling Harmful Microcystis Blooms.

The proliferation of harmful cyanobacterial blooms dominated by Microcystis aeruginosa has become an increasingly serious problem in freshwater ecosystems due to climate change and eutrophication. Microcystis-blooms in freshwater generate compounds with unpleasant odors, reduce the levels of dissolved O, and excrete microcystins into aquatic ecosystems, potentially harming various organisms, including humans. Various chemical and biological approaches have thus been developed to mitigate the impact of the blooms, though issues such as secondary pollution and high economic costs have not been adequately addressed.

sp. nov., isolated from horse faeces.

A Gram-stain-positive, non-spore-forming, and obligate anaerobic bacteria designated strain CBA3647 was isolated from a horse faecal sample in Jeju, Republic of Korea. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain CBA3647 formed a distinct phyletic lineage from closely related species within the genus . Based on comparative analysis of 16S rRNA gene sequences, ATCC 27337 is most closely related to strain CBA3647 with a 16S rRNA gene similarity of 98.

sp. nov. and sp. nov., isolated from marine red algae.

Two Gram-stain-negative, strictly aerobic rods, designated as RMAR6-6 and KMA01, exhibiting catalase- and oxidase-positive activities, were isolated from marine red algae in the Republic of Korea. Cells of strain RMAR6-6 exhibited flagellar motility, while those of strain KMA01 were non-motile. Strain RMAR6-6 exhibited optimal growth at 30-35°C and pH 7.

Enzymatic Activity and Amino Acids Production of Predominant Fungi from Traditional Meju during Soybean Fermentation.

To investigate the effect of the predominant fungal species from Korean traditional meju and doenjang on soybean fermentation, the enzymatic activity and amino acid production of twenty-two fungal strains were assessed through solid- and liquid-state soybean fermentation. Enzymatic activity analyses of solid-state fermented soybeans revealed different enzyme activities involving protease, leucine aminopeptidase (LAP), carboxypeptidase (CaP), glutaminase, γ-glutamyl transferase (GGT), and amylase, depending on the fungal species. These enzymatic activities significantly affected the amino acid profile throughout liquid-state fermentation.

sp. nov. and sp. nov., isolated from a marine red alga.

Two Gram-stain-negative, obligately aerobic, motile rod bacteria, designated as G2-5 and G20-9, exhibiting catalase- and oxidase-positive activities, were isolated from the phycosphere of a species, a marine red alga. Strain G2-5 exhibited optimal growth at 30 °C and pH 5.0-6.

Comparative pangenome analysis of Enterococcus faecium and Enterococcus lactis provides new insights into the adaptive evolution by horizontal gene acquisitions.

Background: Enterococcus faecium and E. lactis are phylogenetically closely related lactic acid bacteria that are ubiquitous in nature and are known to be beneficial or pathogenic. Despite their considerable industrial and clinical importance, comprehensive studies on their evolutionary relationships and genomic, metabolic, and pathogenic traits are still lacking.