Description of Chloramphenicol Resistant Kineococcus rubinsiae sp. nov. Isolated From a Spacecraft Assembly Facility

Abstract

A Gram-positive, coccoid, motile, aerobic bacterium, designated strain B12 T was isolated from a Jet Propulsion Laboratory spacecraft assembly cleanroom, Pasadena, CA, United States. Strain B12 T was resistant to chloramphenicol (100 µg/mL), and is a relatively slow grower (3-5 days optimal). Strain B12 T was found to grow optimally at 28 to 32 • C, pH 7 to 8, and 0.5% NaCl. Fatty acid methyl ester analysis showed that the major fatty acid of the strain B12 T was anteiso C 15:0 (66.3%), which is also produced by other Kineococcus species. However, arachidonic acid (C 20:4 ω6,9,12,16c) was present in strain B12 T and Kineococcus glutinatus YIM 75677 T but absent in all other Kineococcus species. 16S rRNA analysis revealed that strain B12 T was 97.9% similar to Kineococcus radiotolerans and falls within the Kineococcus clade. Low 16S rRNA gene sequence similarities (<94%) with other genera in the family Kineosporiaceae, including Angustibacter (93%), Kineosporia (94% to 95%), Pseudokineococcus (93%), Quadrisphaera (93%), and Thalassiella (94%) demonstrated that the strain B12 T does not belong to these genera. Phylogenetic analysis of the gyrB gene show that all known Kineococcus species exhibited <86% sequence similarity with B12 T. Multi-locus sequence and whole genome sequence analyses confirmed that B12 T clades with other Kineococcus species. Average nucleotide identity of strain B12 T were 75-78% with other Kineococcus species, while values ranged from 72-75% with species from other genera within family Kineosporiaceae. Average amino-acid identities were 66-72% with other Kineococcus species, while they ranged from 50-58% with species from other genera. The dDDH comparison of strain B12 T genome with members of genera Kineococcus showed 20-22% similarity, again demonstrating that B12 T is distantly related to other members of the genus. Furthermore, analysis of whole proteome deduced from WGS places strain B12 T in order Kineosporiales, confirming that strain B12 T is a novel member of family Kineosporiaceae. Based on these analyses and other genome characteristics, strain B12 T is assigned to a novel species within the genus Kineococcus, and the name Kineococcus rubinsiae sp. nov., is proposed. The type strain is B12 T (=FJII-L1-CM-PAB2 T ; NRRL B-65556 T , DSM 110506 T).

Vitreous Magnesium Sulfate Hydrate as a Potential Mechanism for Preservation of Microbial Viability on Europa

“…No evidence of cytoplasmic leakage was detected within the room temperature treatment samples (Figure 6(A)). Additionally, thin filaments are seen that resemble those associated with biofilms or cells that are coated in extracellular polymeric substrates (EPS) and dried out (Mhatre et al 2020;Mettler et al 2022). As P. haloplanktis is not known to form biofilms and was collected in the late log phase of growth, it is more likely that the filaments seen here are small amounts of EPS on the surface of the cells (Figures 6(A) and (B)) and EPS-like fluids that are leaking out of the cells when they undergo traumatic lysing (Figures 6(B) and (C)).…”

Understanding the Complexities and Changes of the Astronaut Microbiome for Successful Long-Duration Space Missions

“…It has been hypothesized that increased virulence and AMR resistance in confined environments, with low microbial diversity, are a result of adaptations that help bacteria and fungi survive in these restricted conditions [320][321][322][323]. These genomic and metabolic changes that occur in confined environments could explain the many novel species that have been identified in various confined habitats [324][325][326][327][328]. Efforts toward design of spacecraft materials to mitigate pathogenic growth would benefit from the prevention of infection rather than relying on treatment after infection, with limited medical resources.…”

Genomic Characterization of Parengyodontium torokii sp. nov., a Biofilm-Forming Fungus Isolated from Mars 2020 Assembly Facility

“…However, while fungal species also produce protective structures (spores, conidia, or cysts) as both part of their life cycle and as a response to environmental stress, few studies have examined their presence on the spacecraft-associated surfaces or their survival under simulated space conditions [4,5]. As a result, several reports on the description of novel bacterial species associated with spacecraft environments were published [6]. Still, systematic characterizations of fungal strains associated with spacecraft environments for their phylogenetic novelty are yet to be conducted.…”