Isolation is the first and crucial step to study possible roles of lactic acid bacteria (LAB) in environment, especially in food fermentation. It is also important to use the organisms for further application. LABs are diverse bacterial group and have diverse growth characteristics. Culture condition of LAB is thus varied, and selection of a suitable culture medium is essential for the purposes. Identification is also important step, since certain desirable and undesirable characteristics are shared within species. Identification was classically carried out by phenotypic characteristics but is usually performed for DNA sequence-based approaches. 16S rRNA gene sequencing is generally used for the identification, and sequencing of housekeeping genes is used when needed. In addition, identification based on whole-genome sequence similarities was well established during the last decade. Here, we describe methods for isolation and identification of LAB briefly.

Here, we present the complete genome sequences and annotations of two species of the Pseudomonas genus isolated from marine and terrestrial environments. Both genomes and their annotations are available on BacBrowse (https://BacBrowse.univ-nantes.fr). This study will contribute to a better understanding of the diversity present within the Pseudomonas genus.

Cell therapy represents a promising treatment modality. A critical component in the production of cell therapy products is maintaining the sterility of cell therapy clean rooms (CTCRs). This study aimed to evaluate the environmental microbial load within CTCRs. We systematically monitored microbial load in CTCRs, following established guidelines. Cultured microbial samples underwent metagenomic sequencing, and alpha and beta diversity analyses, functional annotation, and resistance gene profiling were performed using various bioinformatics tools to assess microbial diversity and function. From November 2023 to January 2024, we collected 42 environmental microbial colony samples from various sources within the CTCR and performed metagenomic sequencing on 39 samples. Alpha diversity analysis revealed no significant differences among surface, settle_plate, and airborne categories, but significant disparities within surface subgroups were revealed. Beta diversity analysis showed notable differences between surface and airborne categories and among surface subgroups. Species distribution analysis identified Bacillus as the predominant genus on surfaces. Functional annotation and resistance gene analysis indicated distinct resistance patterns, with significant variations between subgroups, such as microscopes and transfer windows, and hands and other Grade_B environments. Resistance to hydrogen peroxide was notably higher in the transfer window group. These findings highlight the importance of stringent disinfection protocols and enhanced hand hygiene to maintain sterility in CTCRs. These findings provide valuable insights for implementing effective measures to maintain cleanliness throughout CTCRs. The annotation and study of resistance genes can help rapidly identify methods to control cellular contamination under circumstances of environmental microbial pollution.IMPORTANCEMaintaining the sterility of cell therapy clean rooms (CTCRs) is crucial for the production of safe and effective cell therapy products. Our study systematically evaluated the environmental microbial load within CTCRs, revealing significant microbial diversity and distinct resistance patterns to disinfection methods. These findings underscore the need for stringent disinfection protocols and enhanced hand hygiene practices to ensure CTCR sterility. By identifying key microbial species and their resistance genes, our research provides essential insights into controlling contamination and safeguarding the production environment, ultimately contributing to the reliability and success of cell therapy treatments.

Interactions between bacteria and microalgae are important for the functioning of aquatic ecosystems, yet interactions based on the biodiversity of these two taxonomic domains have been scarcely studied. Specifically, it is unclear whether a positive biodiversity-productivity relationship in phytoplankton is largely facilitated by niche partitioning among the phytoplankton organisms themselves or whether associated bacterial communities play an additional role in modifying these diversity effects. Moreover, the effects of intraspecific diversity in phytoplankton communities on bacterial community diversity have not been tested. To address these points, we factorially manipulated both species and intraspecific richness of three diatoms to test the effects of diatom species/strain diversity on biomass production and bacterial diversity in algae-bacteria communities. The results show that diatom intraspecific diversity has significant positive effects on culture biomass and the diversity of the associated free-living bacterial community (0.2-3 μm size fraction), which are comparable in magnitude to species diversity effects. However, there were little to no effects of diatom diversity on host-associated bacterial diversity (>3 μm size fraction), or of bacterial diversity on biomass production. These results suggest a decoupling of bacterial diversity from the diatom diversity-productivity relationship and provide early insights regarding the relations between diversity across domains in aquatic ecosystems.

Salimicrobium sp. PL1-032A was isolated from Pearse Lakes, Western Australia. The sequenced genome consists of a single chromosome (2,705,688  bp) with a GC content of 47.2%. The isolation of Salimicrobium sp. PL1-032A contributes to the collection of culturable extremophiles and offers potential insight into the Pearse Lakes biome.

The association between human metabolites and the environmental microbiome has primarily been investigated in relation to disease. In this study, the associations between environmental conditions and microbial communities on the surface of bloodstains were analyzed from a forensic science approach. The composition of microbial communities can be affected by numerous variables. After exposing bloodstains to two different environments with limited airflow and human interference, the microbial communities of the bloodstain surfaces were subjected to longitudinal analysis. Various microbes showed increasing or decreasing trends at the phylum and species level. The microbes identified in this study are usually found in soil, freshwater, and seawater and are known to exhibit unique properties, such as sporulation. Longitudinal variation in temperature and humidity were associated with various changes and correlations with the blood surface microbial community. Understanding these changes could introduce a new perspective to forensic science and could be used to develop a forensic tool used at crime scenes to analyze blood stains in more detail.

The geological record of stable carbon isotopes preserved in marine carbonate rocks spans nearly 4 billion years. Numerous perturbations mark this record, but one stands out for its magnitude, the Lomagundi-Jatuli Event, which spanned the transition of the Earth\'s surface from an anoxic to an oxic state. An Applied and Environmental Microbiology article by D. Y. Sumner (90:e00093-24, 2024, https://doi.org/10.1128/aem.00093-24) provides, for the first time, a biological explanation for its initiation, cessation, environmental specific restriction, and geological singularity.

Inspired by the positive impact of serious games on science understanding and motivated by personal interests in scientific outreach, we developed \"Bacttle,\" an easy-to-play microbiology board game with adaptive difficulty, targeting any player from 7 years old onward. Bacttle addresses both the lay public and teachers for use in classrooms as a way of introducing microbiology concepts. The layout of the game and its mechanism are the result of multiple rounds of trial, feedback, and re-design. The final version consists of a deck of cards, a 3D-printed board, and tokens (with a paper-based alternative), with all digital content open source. Players in Bacttle take on the character of a bacterial species. The aim for each species is to proliferate under the environmental conditions of the board and the interactions with the board and with other players, which vary as the play evolves. Players start with a given number of lives that will increase or decrease based on the traits they play for different environmental scenarios. Such bacterial traits come in the form of cards that can be deployed strategically. To assess the impact of the game on microbiological knowledge, we scored differences in the understanding of general concepts before and after playing the game. We assessed a total of 169 visitors at two different university open-day science fairs. Players were asked to fill out a brief survey before and after the game with questions targeting conceptual advances. Results show that Bacttle increases general microbiology knowledge on players as young as 5 years old and with the highest impact on those who have no a priori microbiology comprehension.

In populations of healthy show horses, the subclinical transmission and circulation of respiratory pathogens can lead to disease outbreaks. Due to recent outbreaks of equine herpesvirus-1 myeloencephalopathy (EHM) in the USA and Europe, many show organizers have instituted various biosecurity protocols such as individual horse testing, monitoring for early clinical disease and increasing hygiene and cleanliness protocols. The aim of this study was to determine the accuracy of detecting EHV-1 in the various environmental samples collected from the stalls of subclinical shedders. Four healthy adult horses were vaccinated intranasally with a modified-live EHV-1 vaccine in order to mimic subclinical shedding. Three additional horses served as non-vaccinated controls. All the horses were stabled in the same barn in individual stalls. Each vaccinated horse had nose-to-nose contact with at least one other horse. Prior to the vaccine administration, and daily thereafter for 10 days, various samples were collected, including a 6\" rayon-tipped nasal swab, an environmental sponge, a cloth strip placed above the automatic waterer and an air sample. The various samples were processed for nucleic acid purification and analyzed for the presence of EHV-1 via quantitative PCR (qPCR). EHV-1 in nasal secretions was only detected in the vaccinated horses for 1-2 days post-vaccine administration. The environmental sponges tested EHV-1 qPCR-positive for 2-5 days (median 3.5 days) in the vaccinated horses and 1 day for a single control horse. EHV-1 was detected by qPCR in stall strips from three out of four vaccinated horses and from two out of three controls for only one day. EHV-1 qPCR-positive air samples were only detected in three out of four vaccinated horses for one single day. For the vaccinated horses, a total of 25% of the nasal swabs, 35% of the environmental stall sponges, 7.5% of the strips and 7.5% of the air samples tested qPCR positive for EHV-1 during the 10 study days. When monitoring the subclinical EHV-1 shedders, the collection and testing of the environmental sponges were able to detect EHV-1 in the environment with greater frequency as compared to nasal swabs, stationary strips and air samples.

Human exposure to Vibrio vulnificus, a gram-negative, halophilic environmental pathogen, is increasing. Despite this, the mechanisms of its pathogenicity and virulence remain largely unknown. Each year, hundreds of infections related to V. vulnificus occur, leading to hospitalization in 92% of cases and a mortality rate of 35%. The infection is severe, typically contracted through the consumption of contaminated food or exposure of an open wound to contaminated water. This can result in necrotizing fasciitis and the need for amputation of the infected tissue. Although several genes (rtxA1, vvpE, and vvhA) have been implicated in the pathogenicity of this organism, a defined mechanism has not been discovered. In this study, we examine environmentally isolated V. vulnificus strains using a zebrafish model (Danio rerio) to investigate their virulence capabilities. We found significant variation in virulence between individual strains. The commonly used marker gene of disease-causing strains, vcgC, did not accurately predict the more virulent strains. Notably, the least virulent strain in the study, V. vulnificus Sept WR1-BW6, which tested positive for vcgC, vvhA, and rtxA1, did not cause severe disease in the fish and was the only strain that did not result in any mortality. Our study demonstrates that virulence varies greatly among different environmental strains and cannot be accurately predicted based solely on genotype.