Explore the vast range of titles available.

Estrogens, particularly 17β-estradiol, are prevalent endocrine-disrupting chemicals in aquatic environments, posing risks to ecosystems and human health. Biodegradation is considered one of the most effective and environmentally friendly methods for removing estrogen. In this study, a novel bacterial strain, Microbacterium proteolyticum ZJSU01, was isolated from pig manure. It completely degraded 5 mg/L of 17β-estradiol (E2) within 4 h, as well as its major transformation product, estrone (E1). The strain ZJSU01 displayed strong adaptability to high temperatures (37℃, 42℃) and a broad pH range (6–11), E2 (5 mg/L) could be completely removed by the strain under these conditions. Transformation intermediates were analyzed using UHPLC and HPLC-Q-TOF–MS to identify key metabolites and trace the degradation pathways. Four potential degradation pathways were identified, including the 4,5-seco pathway, which is widely conserved in most E2-degrading bacteria. Whole-genome sequencing predicted a chromosome with a size of 3,828,432 bp, and a series of functional genes, and transcriptomics analysis identified several genes involved in E2 degradation. The budC gene, a member of the short-chain dehydrogenases/reductases (SDRs) family, was identified as critical for E2 degradation and exhibited a nearly 170-fold upregulation. Meanwhile, genes such as fdeE and catA were associated with downstream degradation. Microbacterium proteolyticum ZJSU01 demonstrated strong acid–base and high-temperature resilience, highlighting its strong potential for practical applications due to its degradation capability and adaptability. This strain could be applied in wastewater treatment to effectively remove estrogenic pollutants from contaminated water. Key points • Microbacterium proteolyticum ZJSU01 removed 100% of E2 (10、5、1 mg/L) within 4 h. • Strain ZJSU01 showed great tolerance to high temperature and acid–base conditions. • A novel gene, budC , was identified as the primary driver of E2 degradation by ZJSU01.

There are reports on resistance to metals by the Microbacteriaceae family, although few studies have focused on the Microbacterium genus. The present work is one of the first studies related to arsenic (As) resistance and removal by Microbacterium hydrocarbonoxydans . Growth curves were performed simultaneously as follows: (1) growth kinetics without As, and (2) growth kinetics added with As(III). Incubation conditions were at 30 °C and 120 rpm for 168 h, with an inoculation of bacterial culture, 107 (CFU)/ml. Absorbance was measured at 600 nm in an ultraviolet (UV)–vis spectrophotometer. The As surface adsorption and uptake into bacterial cells, exposed to As(III), were confirmed through SEM, EDX, and FTIR analyses. It was observed that the cellular morphology of M. hydrocarbonoxydans through TEM was deformed when exposed to high concentrations of arsenite. Bacterial cells growing in a rich medium with As(III) were able to oxidize 98% As(III), and the inactivated biomass of the bacterium exhibited a high removal capacity. Likewise, M. hydrocarbonoxydans was employed to test its ability to remove other toxic heavy metals such as lead, cadmium, and chromium. The order of resistance of each metal was as follows: Cr VI (2.08 gL −1 ) > Pb (1.24 gL −1 ) > Cd (0.169 gL −1 ). This work demonstrated that the strain M. hydrocarbonoxydans has high arsenic resistance and removal capacity, as well as significant As(III) oxidation potential, rendering it a promising candidate for biotechnological application in the development of affordable systems for the removal of metals/metalloids from contaminated sites.

Strain M28 T was isolated from subsoil obtained from decaying wheat straw. Cells were Gram-positive, non-motile, short rod-shaped and formed yellowish colonies on lysogeny broth (LB) agar. The strain was able to grow at 0–8% (w/v) NaCl , 15–40 °C and pH 5.5–10.0. Phylogenetic analysis based on 16S rRNA gene sequences, core genes and whole-genome indicated that strain M28 T belonged to the genus Microbacterium but was distinct from all known strains in this genus. Based on phenotypic, genotypic, chemical taxono mic and phylogenetic analyses, strain M28 T is a representative of a new species of Microbacterium , which is proposed to be named Microbacterium triticisoli sp. nov., the type strain is M28 T (=CCTCC AA 2022021 T =JCM 35796 T ). Genomic analysis revealed multiple metal resistance systems, antibiotic resistance determinants and oxidative stress defense genes, explaining its exceptional environmental adaptability. Notably, the strain reduced 99% of 50 mg/L Cr(VI) within 24 h under optimized conditions (37 °C, pH 7.0, 2.5 g/L sucrose) and tolerated Cr(VI) concentrations up to 125 mg/L. This study identifies M. triticisoli as a promising agent for chromium bioremediation, providing a foundation for engineering microbial solutions to heavy metal pollution.

During the microbial surveillance of the International Space Station (ISS) in April 2018, four Gram-stain positive bacterial strains, designated as F6_8S_P_2B T , F6_8S_P_3A, F6_8S_P_3B and F6_8S_P_3C, belonging to the genus Microbacterium were isolated from the walls of crew quarters. All four strains exhibited high 16S rRNA gene sequence similarity (> 99%), low average nucleotide identity (93%), and < 49.7% digital DNA: DNA hybridization values with the closest recognized Microbacterium paraoxydans DSM 15019 T , delineating new phylogenetic branches within the genus. Further whole-genome sequencing (WGS) and phylogenomic analysis revealed a close genetic relationship (> 98% ANI; > 83% dDDH) between the ISS strains and Microbacterium sp. LTR1 strain isolated from the larva skin of Lissotriton vulgaris from Tula region, Russia, which was misidentified as M. paraoxydans . The pangenomic analysis also shows high correlation between the ISS strains and their proximity to the type strain M. paraoxydans DSM 15019 T . These analyses suggest that strain LTR1, previously characterized as M. paraoxydans , should be included in this new Microbacterium clade alongside the four novel ISS strains. Functional genome analysis revealed unique proteins associated with transcription, defense, and metabolism. The genome harbored toxin-antitoxin modules (e.g., VapBC, Phd/YuzE), stress response regulators (FrmR, YhcF), and genes involved in formaldehyde resistance and glycoside hydrolase activity. Secondary metabolite gene clusters included beta-lactone, terpene, and T3PKS. Notably, tetracycline resistance gene tet(42) was present, indicating potential clinical relevance. The ISS strains grew at 4–40 °C, 0.5–8% NaCl, and pH 6.0–9.0. Chemotaxonomic features included anteiso-C15:0 and anteiso-C17:0 as major fatty acids, MK-12 as the predominant menaquinone, and ornithine as the diagnostic diamino acid in B2β-type peptidoglycan. The genomic DNA G+C content was 70.03 mol%. The polyphasic taxonomy showed that the ISS isolates along with LTR1 represent distinct strains of a new Microbacterium species, herein named Microbacterium meiriae. The type strain is F6_8S_P_2B T (DSM 115935 T  = NRRL B-65668 T ).

The genus Microbacterium in the phylum Actinomycetota contains over 100 species to date that little is known about their bioactive metabolites production. In this study, a mangrove sediment-derived strain B2969 T was identified as a novel type strain within the genus Microbacterium due to the low 16S rRNA gene sequence similarity (< 99%), and low overall genome relatedness indices (ANI, 75.4%-79.5%; dDDH, 18.5%-22.7%, AAI, 68.7%-76.3%; POCP, 48.3%-65.0%) with the validly named species of the genus. The type strain B2969 T (= MCCC 1K099113 T  = JCM 36707  T ) is proposed to represent Microbacterium alkaliflavum sp. nov.. The crude extracts of strain B2969 T showed weak cytotoxicity against NPC cell lines TW03 and 5-8F, with IC 50 values of ranging from 3.5 µg/µL to 2.4 µg/µL respectively. Genome analysis of strain B2969 T found 8 clusters of genes responsible for secondary metabolite biosynthesis, including cytotoxic compounds desferrioxamines. In addition, the application of liquid chromatography tandem mass spectrometry (LC–MS/MS)-based molecular networking strategy led to the identification of 10 compounds with potent cytotoxic activity in ethyl acetate extracts of strain B2969 T . Results from the cytotoxicity assay, genome mining, and metabolite profiling based on LC–MS/MS analysis revealed its ability to produce bioactive compounds. Background Mangrove ecosystems are largely unexplored sources of Actinomycetota , which represent potential important reservoirs of bioactive compounds. The genus Microbacterium in the phylum Actinomycetota contains over 100 species to date that little is known about their bioactive metabolites production. In this study, a novel species, namely B2969 T , within the genus Microbacterium that showed cytotoxicity against nasopharyngeal carcinoma (NPC) cell lines was isolated from mangrove sediments. Genome mining and metabolic profiling analyses were explored here to assess its biosynthetic potential of metabolites with cytotoxic properties. Results Here, a mangrove sediment-derived strain B2969 T was identified as a novel species within the genus Microbacterium due to the low 16S rRNA gene sequence similarity (< 99.0%), and low overall genome relatedness indices (ANI, 75.4%-79.5%; dDDH, 18.5%-22.7%, AAI, 68.7%-76.3%; POCP, 48.3%-65.0%) with the type strains of this genus. We proposed that strain B2969 T represents a new species, in which the name Microbacterium alkaliflavum sp. nov. is proposed. The strain showed weak cytotoxicity against NPC cell lines TW03 and 5-8F, with IC 50 values of ranging from 3.512 µg/µL to 2.428 µg/µL respectively. Genome analysis of strain B2969 T found 8 clusters of genes responsible for secondary metabolite biosynthesis, including desferrioxamines. In addition, the application of liquid chromatography tandem mass spectrometry (LC–MS/MS)-based molecular networking strategy led to the identification of 10 potent cytotoxic compounds in ethyl acetate extracts of strain B2969 T . Conclusions This study confirmed the taxonomy status of type strain B2969 T (= MCCC 1K099113 T  = JCM 36707  T ) within the genus Microbacterium , in which the name Microbacterium alkaliflavum sp. nov.. Results from the cytotoxicity assay, genome mining, and metabolite profiling based on LC–MS/MS analysis revealed its ability to produce bioactive substances, providing sufficient evidence for the potential of Microbacterium species in the discovery of novel pharmaceuticals.

A promising bacterial strain for biodegrading dibutyl phthalate (DBP) was successfully isolated from activated sludge and characterized as a potential novel Microbacterium sp. USTB-Y based on 16S rRNA sequence analysis and whole genome average nucleotide identity (ANI). Initial DBP of 50 mg/L could be completely biodegraded by USTB-Y both in mineral salt medium and in DBP artificially contaminated soil within 12 h at the optimal culture conditions of pH 7.5 and 30 ℃, which indicates that USTB-Y has a strong ability in DBP biodegradation. Phthalic acid (PA) was identified as the end-product of DBP biodegraded by USTB-Y using GC/MS. The draft genome of USTB-Y was sequenced by Illumina NovaSeq and 29 and 188 genes encoding for putative esterase/carboxylesterase and hydrolase/alpha/beta hydrolase were annotated based on NR (non redundant protein sequence database) analysis, respectively. Gene3781 and gene3780 from strain USTB-Y showed 100% identity with dpeH and mpeH from Microbacterium sp. PAE-1. But no phthalate catabolic gene (pht) cluster was found in the genome of strain USTB-Y. The results in the present study are valuable for obtaining a more holistic understanding on diverse genetic mechanisms of PAEs biodegrading Microbacterium sp. strains.

Crew members are at an increased risk for exposure to and infection by pathogenic microbes during spaceflight. Therefore, it is imperative to characterize the species that are able to colonize and persist on spacecraft, how those organisms change in abundance and distribution over time, and their genotypic potential for and phenotypic expression of pathogenic traits (i.e., whether they encode for or exhibit traits associated with antibiotic resistance and/or virulence). Here, we describe a novel species of Microbacterium collected from the crew quarters on the International Space Station (ISS), 1F8SW-P5 T , for which we propose the name Microbacterium mcarthurae . M. mcarthurae was found to be distributed throughout the ISS with an increase in relative abundance over time. Additionally, this bacterium exhibits a unique antibiotic resistance phenotype that was not predicted from whole-genome sequencing, as well as increased virulence, suggesting the need for the identification of previously undescribed antimicrobial resistance genes and monitoring/mitigation during spaceflight.

The green marine macroalgae of the class Ulvophyceae (Ulvophytes) are common algae distributed worldwide particularly in intertidal areas, which play a key role in aquatic ecosystems. They are potentially valuable resources for food, animal feed and fuel but can also cause massive nuisance blooms. Members of Ulvaceae, like many other seaweeds, harbour a rich diversity of epiphytic bacteria with functions related to host growth and morphological development. In the absence of appropriate bacterially derived signals, germ cells of the genus Ulva develop into 'atypical' colonies consisting of undifferentiated cells with abnormal cell walls. This paper examines the specificity of bacteria-induced morphogenesis in Ulva, by cross-testing bacteria isolated from several Ulva species on two Ulva species, the emerging model system Ulva mutabilis and the prominent biofouler species Ulva intestinalis. We show that pairs of bacterial strains isolated from species other than U. mutabilis and U. intestinalis can fully rescue axenic plantlets generated either from U. mutabilis or U. intestinalis gametes. This laboratory-based study demonstrates that different compositions of microbial communities with similar functional characteristics can enable complete algal morphogenesis and thus supports the 'competitive lottery' theory for how symbiotic bacteria drive algal development.

Biofilms that form on roots, litter and soil particles typically contain multiple bacterial species. Currently, little is known about multispecies biofilm interactions and few studies have been based on environmental isolates. Here, the prevalence of synergistic effects in biofilm formation among seven different soil isolates, cocultured in combinations of four species, was investigated. We observed greater biofilm biomass production in 63% of the four-species culture combinations tested than in biofilm formed by single-species cultures, demonstrating a high prevalence of synergism in multispecies biofilm formation. One four-species consortium, composed of Stenotrophomonas rhizophila , Xanthomonas retroflexus , Microbacterium oxydans and Paenibacillus amylolyticus, exhibited strong synergy in biofilm formation and was selected for further study. Of the four strains, X. retroflexus was the only one capable of forming abundant biofilm in isolation, under the in vitro conditions investigated. In accordance, strain-specific quantitative PCR revealed that X. retroflexus was predominant within the four-species consortium (>97% of total biofilm cell number). Despite low relative abundance of all the remaining strains, all were indispensable for the strong synergistic effect to occur within the four-species biofilm. Moreover, absolute individual strain cell numbers were significantly enhanced when compared with those of single-species biofilms, indicating that all the individual strains benefit from inclusion in the multispecies community. Our results show a high prevalence of synergy in biofilm formation in multispecies consortia isolated from a natural bacterial habitat and suggest that interspecific cooperation occurs.

After cleaning and disinfection (C&D), surface contamination can still be present in the production environment of food companies. Microbiological contamination on cleaned surfaces can be transferred to the manufactured food and consequently lead to foodborne illness and early food spoilage. However, knowledge about the microbiological composition of residual contamination after C&D and the effect of this contamination on food spoilage is lacking in various food sectors. In this study, we identified the remaining dominant microbiota on food contact surfaces after C&D in seven food companies and assessed the spoilage potential of the microbiota under laboratory conditions. The dominant microbiota on surfaces contaminated at ≥10 CFU/100 cm after C&D was identified based on 16S rRNA sequences. The ability of these microorganisms to hydrolyze proteins, lipids, and phospholipids, ferment glucose and lactose, produce hydrogen sulfide, and degrade starch and gelatin also was evaluated. Genera that were most abundant among the dominant microbiota on food contact surfaces after C&D were Pseudomonas, Microbacterium, Stenotrophomonas, Staphylococcus, and Streptococcus. Pseudomonas spp. were identified in five of the participating food companies, and 86.8% of the isolates evaluated had spoilage potential in the laboratory tests. Microbacterium and Stenotrophomonas spp. were identified in five and six of the food companies, respectively, and all tested isolates had spoilage potential. This information will be useful for food companies in their quest to characterize surface contamination after C&D, to identify causes of microbiological food contamination and spoilage, and to determine the need for more thorough C&D.