Project description:We obtained L. kefiri (JCM5818) and L. kefiranofaciens (JCM6985) from the Japan Collection of Microorganisms (JCM). Bacteria were grown together at two different temperatures of 30C and 37C profiled for transcriptomics, metabolomics, and proteomics.
Project description:Previous studies have demonstrated that the iron content in marine heterotrophic bacteria is comparatively higher than that of phytoplankton. Therefore, they have been indicated to play a major role in the biogeochemical cycling of iron. In this study, we aimed to investigate the potential of viral lysis as a source of iron for marine heterotrophic bacteria. Viral lysates were derived from the marine heterotrophic bacterium, Vibrio natriegens PWH3a (A.K.A Vibrio alginolyticus). The bioavailability of Fe in the lysates was determined using a model heterotrophic bacterium, namely, Dokdonia sp. strain Dokd-P16, isolated from Fe-limited waters along Line P transect in the Northeastern Pacific Ocean. The bacteria were grown under Fe-deplete or Fe-replete conditions before being exposed to the viral lysate. Differential gene expression following exposure to the viral lysate was analyzed via RNA sequencing to identify differentially expressed genes under iron-replete and iron-deplete conditions. This study would provide novel insights into the role of viral lysis in heterotrophic bacteria in supplying bioavailable iron to other marine microorganisms under iron-limiting and non-limiting conditions. First, the marine heterotrophic bacterium genome, Dokdonia sp. strain Dokd-P16, was sequenced to provide a genomic context for the expression studies. Subsequently, the relative gene expression in Dokdonia sp. strain Dokd-P16 grown under Fe limiting and non-limiting conditions were analyzed. This transcriptomic approach would be utilized to elucidate genes regulated by Fe availability in Dokdonia sp. strain Dokd-P16, which indicate its Fe-related response viral lysate exposure. Taken together, in this study, the transcriptomic responses of Fe-limited and non-limited marine heterotrophic bacteria were analyzed, which provided novel insights into the biological availability of Fe from the viral lysates.
Project description:Marine is one of the most important resources of microorganisms, including bacteria, actinomycetes, and fungi. As marine and terrestrial environments differ a lot in many aspects it is not surprising that the species and characteristics of microorganisms living there are very different. Interestingly, many marine microorganisms can find their congeners of the same species from terrestrial resources. The aim of this work is to evaluate the intraspecies differences between marine and terrestrial actinomycetes on metabolic level and to uncover the mechanism responsible for the differences. To address this, we carried out comparative metabolomics study on Nesterenkonia flava strains isolated from marine and terrestrial environments. The results showed that marine strains were clearly distinguished from their terrestrial congeners on the principal components analysis (PCA) scores plot of intracellular metabolites. The markers responsible for the discrimination of marine and terrestrial strains were figured out using loading plot from partial least squares discrimination analysis (PLS-DA). Pathway analysis based on PLS-DA, univariate analysis, and correlation analysis of metabolites showed that the major differential metabolites between the terrestrial N. flava and the marine ones were involved in osmotic regulation, redox balancing, and energy metabolism. Together, these insights provide clues as to how the previous living environment of microbes affect their current metabolic performances under laboratory cultivation conditions.
Project description:Light was a ubiquitous environmental stimulus. Deep-sea microorganisms were exposed to a pervasive blue light optical environment. The utilization of blue light by deep-sea microorganisms, especially non-photosynthetic microorganisms, and the downstream pathway after light reception were obscure. Under the enrichment condition surrounded by blue light, a potential novel species named Spongiibacter nanhainus CSC3.9 from the deep-sea cold seep was isolated. Its growth and metabolism under blue light were significantly better than other wavelengths of light. Six blue light sensing proteins, including four BLUF (Blue Light Using Flavin) and two bacteriophytochrome, were annotated in the genome of strain CSC3.9. Then, with the assist of proteomic analysis, we demonstrated that 15960-BLUF was a crucial blue light receptor that interfered with motor behavior through chemotaxis pathway by means of in vivo and in vitro verification. In addition, 15960-BLUF mediated part of the blue light to promote the growth of strain CSC3.9. Further, we summarized the functional BLUF proteins from isolated marine microorganisms, and the high abundance distribution of BLUF similar to the downstream unresponsive domain type in strain CSC3.9 was demonstrated. The widespread distribution of BLUF protein in marine bacteria implied the extensiveness of this regulatory mechanism, and wavelength variation of light was a potential means to isolate uncultured microorganisms. This was the first reported in deep-sea microorganisms that BLUF-dependent physiological response to blue light. It provided a new clue for the blue light adaptation of microorganisms in disphotic zone.
2022-01-18 | PXD028001 | Pride
Project description:Genome sequencing of bacteria from the Russian Collection of Agricultural Microorganisms
Project description:Osmotic changes are common challenges for marine microorganisms. Bacteria developed numerous ways of dealing with this stress, including reprogramming of global cellular processes, however, many molecular details were obtained only for the model bacteria. In this work we asked what is the basis of the adjustment to prolonged salinity challenges at the proteome level. The objects of our studies were three representatives of bacteria inhabiting various marine environments, Shewanella baltica, Vibrio harveyi and Aliivibrio fischeri. The proteomic studies were performed with bacteria cultivated in increased and decreased salinity, followed by proteolytic digestion of samples which were then subjected to liquid chromatography with tandem mass spectrometry analysis. We show that bacteria adjust at all levels of their biological processes, from DNA topology through gene expression regulation and proteasome assembly, to transport and cellular metabolism. Finding that many similar adaptation strategies were observed for both, low and high salinity conditions, is particularly interesting. The results show that adaptation to salinity challenge involves accumulation of DNA-binding proteins and increased polyamine uptake, and we hypothesize that their function is to coat and protect the nucleoid to counteract adverse changes in the DNA topology due to ionic shifts.
2022-02-17 | PXD029628 | Pride
Project description:Airborne microorganisms from waste collection facility