ExtremophilesPub Date : 2024-12-21DOI: 10.1007/s00792-024-01377-9
Caroline Martiniuc, Igor Taveira, Fernanda Abreu, Anderson S Cabral, Rodolfo Paranhos, Lucy Seldin, Diogo Jurelevicius
{"title":"Insights into the dynamics and evolution of Rummeliibacillus stabekisii prophages in extreme environments: from Antarctic soil to spacecraft floors.","authors":"Caroline Martiniuc, Igor Taveira, Fernanda Abreu, Anderson S Cabral, Rodolfo Paranhos, Lucy Seldin, Diogo Jurelevicius","doi":"10.1007/s00792-024-01377-9","DOIUrl":"https://doi.org/10.1007/s00792-024-01377-9","url":null,"abstract":"<p><p>Since prophages can play a multifaceted role in bacterial evolution, this study aims to characterize the virome of Rummeliibacillus stabekisii, a bacterium isolated from different environments, including Antarctic soil and NASA spacecraft floors. From the analyses, it was found that the Antarctic strain, PP9, had the largest number of prophages, including intact ones, indicating potential benefits for survival in adverse conditions. In contrast, other strains harbored predominantly degenerate prophages, suggesting a dynamic process of gene gain and loss during evolution. Furthermore, strain PP9 exhibited polylysogeny, a strategy capable of increasing its competitive advantage by providing a broader spectrum of defensive mechanisms. In addition, evidence demonstrates that prophage regions in PP9 act as hotspots for recombination events, favoring the insertion of different phages and possible antimicrobial resistance genes. Finally, lytic cycle induction experiments revealed at least two intact prophages active in PP9. In this way, understanding the interaction between viruses and bacteria can provide valuable information about microbial evolution and adaptation in extreme environments, such as Antarctica.</p>","PeriodicalId":12302,"journal":{"name":"Extremophiles","volume":"29 1","pages":"10"},"PeriodicalIF":2.6,"publicationDate":"2024-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142871903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ExtremophilesPub Date : 2024-12-19DOI: 10.1007/s00792-024-01375-x
María Gabriela Brito, Nancy I López, Laura J Raiger Iustman
{"title":"Unraveling the effects of polyhydroxyalkanoates accumulation in Pseudomonas extremaustralis growth and survival under different pH conditions.","authors":"María Gabriela Brito, Nancy I López, Laura J Raiger Iustman","doi":"10.1007/s00792-024-01375-x","DOIUrl":"https://doi.org/10.1007/s00792-024-01375-x","url":null,"abstract":"<p><p>Polyhydroxyalkanoates (PHAs) are intracellular polymers that enhance bacterial fitness against various environmental stressors. Pseudomonas extremaustralis 14-3b is an Antarctic bacterium capable of accumulating, short-chain-length PHAs (sclPHAs), composed of C3-C5 monomers, as well as medium-chain-length PHAs (mclPHAs) containing ≥ C6 monomers. Since pH changes are pivotal in bacterial physiology, influencing microbial growth and metabolic processes, we propose that accumulated PHA increases P. extremaustralis fitness to cope with pH changes. To test this, we analyzed the production of sclPHA and mclPHA at different pH levels and its effect on bacterial survival against pH stress. P. extremaustralis was able to grow and accumulate PHA when the culture media pH ranged from 6.0 to 9.5, showing a marked loss of viability outside this range. Additionally, based on the analysis of different PHA-deficient mutants, we found that when exposed to both acidic and alkaline conditions, sclPHA and mclPHA conferred different protection against pH stress, with sclPHA making the main contribution. These results highlight the importance of PHA in supporting survival in pH-stressful environments.</p>","PeriodicalId":12302,"journal":{"name":"Extremophiles","volume":"29 1","pages":"9"},"PeriodicalIF":2.6,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142853071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ExtremophilesPub Date : 2024-12-13DOI: 10.1007/s00792-024-01374-y
James A Raymond
{"title":"Variations on a theme: non-canonical DUF3494 ice-binding proteins.","authors":"James A Raymond","doi":"10.1007/s00792-024-01374-y","DOIUrl":"10.1007/s00792-024-01374-y","url":null,"abstract":"<p><p>Among the many ice-binding proteins (IBPs) found in microorganisms (bacteria, archaea, fungi and algae), the canonical DUF3494 beta-barrel type is the most common. Until now, little variation has been found in this structure: an initial coil leads into an alpha helix that directs the following coils into a reverse stack, with the final coil ending up next to the initial coil. Here, I show that there exist many bacterial proteins whose AlphaFold-predicted structures deviate from the DUF3494 structure so that they are not recognized as belonging to an existing DUF or Pfam family. In these non-canonical DUF3494 (ncDUF3494) proteins, the number of coils in the alpha helix is highly variable, often being as high as 14. The putative ice-binding sides of each of 13 proteins modeled have a well-aligned row of hydrophilic residues, with spacings that are close to the repeat distance on the ice a-axis. A recombinant protein made for one of the proteins showed that it had ice-binding activity, even in the µg/ml range. The ncDUF3494 proteins appear to be found only in bacteria, the great majority of which live in icy habitats. C-terminal PEP-Cterm motifs, which are rare in DUF3494s, are present in most of the ncDUF3494s, possibly indicating a secretory function. The relatively narrow distribution of ncDUF3494 proteins suggests that they are a later development in DUF3494 evolution.</p>","PeriodicalId":12302,"journal":{"name":"Extremophiles","volume":"29 1","pages":"8"},"PeriodicalIF":2.6,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11645318/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142817296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Characterization of a family IV esterase from extremely halophilic archaeon Haloarcula japonica.","authors":"Hiromichi Kato, Shota Ambai, Fumiya Ikeda, Koji Abe, Satoshi Nakamura, Rie Yatsunami","doi":"10.1007/s00792-024-01370-2","DOIUrl":"10.1007/s00792-024-01370-2","url":null,"abstract":"<p><p>The novel esterase gene lipP1, which encodes HjEstP1, was discovered in the genome of the extremely halophilic archaeon Haloarcula japonica. A homology search and sequence alignment revealed that HjEstP1 is a member of family IV esterases with conserved GXSXG and HGGG motifs. lipP1 was expressed in its parental strain, and recombinant HjEstP1 was purified and characterized. Optimal pH and temperature of HjEstP1 were 6.0 and > 60 °C, respectively. HjEstP1 showed higher activity with increasing NaCl concentration, and optimal NaCl concentration was > 4.5 M. Furthermore, HjEstP1 preferentially hydrolyzed pNP and glycerol esters with short chain fatty acids. To our knowledge, this is the first report of an esterase from an extremely halophilic archaeon obtained via homologous expression.</p>","PeriodicalId":12302,"journal":{"name":"Extremophiles","volume":"29 1","pages":"7"},"PeriodicalIF":2.6,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11614938/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142767594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ExtremophilesPub Date : 2024-11-27DOI: 10.1007/s00792-024-01369-9
Gunisha Wadhawan, Anshu Gupta
{"title":"Biological treatment of methyl orange dye and textile wastewater using halo-alkaliphilic bacteria under highly alkaline conditions.","authors":"Gunisha Wadhawan, Anshu Gupta","doi":"10.1007/s00792-024-01369-9","DOIUrl":"https://doi.org/10.1007/s00792-024-01369-9","url":null,"abstract":"<p><p>As the textile wastewater is highly saline and has high pH it is important to employ extremophilic microbes to survive in harsh conditions and provide effective bioremediation of textile dyes. This study aims to find a sustainable solution for dye removal by investigating the potential of an indigenously isolated bacterium, Nesterenkonia lacusekhoensis EMLA3 (halo-alkaliphilic) for treatment of an azo dye, methyl orange (MO) and textile effluent. MO dye decolorization studies were conducted using mineral salt media (MSM) by varying incubation time (0-120 h), initial dye concentration (50-350 mg/L), pH (7.0-12.0), inoculum dose (3-10%), agitation (stationary, 100 rpm and 200 rpm), and temperature (20-55 °C). Dye removal by the bacterium for 50 mg/L of dye was > 97.0% within 72 h of incubation at pH 11.0 in stationary condition. Bacterium had excellent reusability i.e. > 97% dye removal for up to 5 cycles. Moreover, bacterium has the potential for co-removal of chromium (VI) (3.5-28 mg/L), and also almost complete dye removal in presence of high amount of NaCl. Liquid chromatography-mass spectrometry showed degradation as the mechanism of dye removal. Application of the bacterium to MO dye spiked real textile wastewater showed excellent dye removal. Phyto-toxicity assessment conducted on Vigna radiata and Triticum aestivum seeds, showed 100% germination of biotreated textile wastewater indicating its reuse potential.</p>","PeriodicalId":12302,"journal":{"name":"Extremophiles","volume":"29 1","pages":"6"},"PeriodicalIF":2.6,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142727124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ExtremophilesPub Date : 2024-11-26DOI: 10.1007/s00792-024-01364-0
Russell H Vreeland, Aharon Oren, Antonio Ventosa
{"title":"Lawrence I. (Larry) Hochstein a researcher dedicated to halophilic microorganisms of all types and environments.","authors":"Russell H Vreeland, Aharon Oren, Antonio Ventosa","doi":"10.1007/s00792-024-01364-0","DOIUrl":"https://doi.org/10.1007/s00792-024-01364-0","url":null,"abstract":"","PeriodicalId":12302,"journal":{"name":"Extremophiles","volume":"29 1","pages":"5"},"PeriodicalIF":2.6,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142715901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ExtremophilesPub Date : 2024-11-23DOI: 10.1007/s00792-024-01371-1
Alessia Rossi, Irene Barbagli, Claudia Vannini
{"title":"Characterization of prokaryotic communities from Italian super-heated fumaroles.","authors":"Alessia Rossi, Irene Barbagli, Claudia Vannini","doi":"10.1007/s00792-024-01371-1","DOIUrl":"https://doi.org/10.1007/s00792-024-01371-1","url":null,"abstract":"<p><p>Among extremophiles, thermophile microorganisms from geothermal sites have been widely studied. Nevertheless, our knowledge is still relatively poor on microbial communities colonizing fumaroles, which are super-ephemeral habitats, characterized by an only intermittent presence of water. Here we characterized by metabarcoding both bacterial and archaeal communities from hot spring waters and biofilms, together with dry and wet fumaroles, of a geothermal basin in central Italy. Taxa composition of the analyzed samples mirrored that of previous studies, with Thermoproteota dominating among Archaea, while high percentages of thermophiles and spore-forming organisms were retrieved for Bacteria. Cyanobacteriota were the dominant group in biofilms. Community structure was different in the two domains, with highly selected communities of Archaea, less diversified than bacterial ones. Linear regression analyses highlighted significant correlations between diversity and environmental parameters in dry, but not in wet fumaroles. Although ASV numbers displayed different trends for the two different prokaryotic domains (positive correlation with pH for Bacteria, negative correlation for both pH and T for Archaea), such results indicate that even an extremely ephemeral presence of water can influence the importance of temperature and pH as drivers for microbial community structure.</p>","PeriodicalId":12302,"journal":{"name":"Extremophiles","volume":"29 1","pages":"4"},"PeriodicalIF":2.6,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142695359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Increase of ATP synthesis and amino acids absorption contributes to cold adaptation in Antarctic bacterium Poseidonibacter antarcticus SM1702<sup>T</sup>.","authors":"Wen-Yue Xu, Sha-Sha Liu, Xiao-Han Guo, Peng Wang, Chun-Yang Li, Li Liao, Qi-Long Qin","doi":"10.1007/s00792-024-01372-0","DOIUrl":"10.1007/s00792-024-01372-0","url":null,"abstract":"<p><p>Numerous psychrophiles inhabit the cold environments that are prevalent across the global biosphere. The adaptation of psychrophiles to cold conditions has been widely studied in strains from the archaeal phylum Euryarchaeota and the bacterial class Gamma-proteobacteria. However, given the vast diversity of microorganisms in cold environments, many microbial lineages with potentially unique cold-adaptation strategies remain largely unexplored. This study investigates the cold responses of the Antarctic strain Poseidonibacter antarcticus SM1702<sup>T</sup>, a cold-adapted bacterium belonging to the class Epsilon-proteobacteria within the phylum Campylobacterota. Proteomic analysis revealed that this strain responds to low temperatures by overexpressing proteins involved in energy production and amino acid transport. Experimental results confirmed that intracellular ATP concentrations increased at low temperatures compared to higher temperatures. Low temperatures significantly reduced the strain's amino acid absorption rates, a condition that was mitigated by increased expression of membrane transporters. We propose that the impairment of membrane protein function due to low temperatures is the primary factor affecting cell growth. As a result, the strain enhances ATP synthesis and upregulates membrane transporter expression to counteract cold stress. These findings contribute to a deeper understanding of cold adaptation strategies in psychrophiles.</p>","PeriodicalId":12302,"journal":{"name":"Extremophiles","volume":"29 1","pages":"3"},"PeriodicalIF":2.6,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142686633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ExtremophilesPub Date : 2024-11-21DOI: 10.1007/s00792-024-01373-z
C Sriaporn, S Komonjinda, N Klayposri, K Phinyo, J Pekkoh, S Awiphan, T Chanprom
{"title":"Microbial and mineralogical characterization of the alkaline Chae Son hot spring, Northern Thailand.","authors":"C Sriaporn, S Komonjinda, N Klayposri, K Phinyo, J Pekkoh, S Awiphan, T Chanprom","doi":"10.1007/s00792-024-01373-z","DOIUrl":"https://doi.org/10.1007/s00792-024-01373-z","url":null,"abstract":"<p><p>Early characterizations by morphological identification through light microscopy only revealed the presence of a few microbial lineages and the majority of microbial community at the Chae Son hot spring remains uncharacterized. Therefore, this study aims to examine thermophilic microbial communities at the Chae Son hot spring using next-generation sequencing, including investigating hot spring mineralogy. Results suggest that the Chae Son hot spring (49-75 °C, pH = 6.5-7.0) precipitates digitate structures which comprise mainly silica, and that microbial permineralization is primarily through silicification. Alternating layers of mineralized microbial biofilms and silica were observed in digitate sinter cross-sections, contributing to the build-up of microstromatolites. Molecular results revealed that phylogenetically distinct members of photoautotrophic taxa, Chloroflexota and Cyanobacteriota, dominated spring microbial communities (63.19% relative abundance). Potential primary production processes were mainly through photoautotrophy, with minor lithoautotrophic activities (e.g., sulfur cycling and nitrogen cycling). Moreover, overall microbial community and Cyanobacteriota population alpha diversities significantly decreased with increased temperatures. However, no significant correlation was identified between Chloroflexota population diversity and temperatures. This study provides an update on the microbial community using a high-throughput next-generation sequencing technology, including the mineralogy of the Chae Son hot spring, Northern Thailand.</p>","PeriodicalId":12302,"journal":{"name":"Extremophiles","volume":"29 1","pages":"2"},"PeriodicalIF":2.6,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142681208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Insights into the role of cyclopropane fatty acid synthase (CfaS) from extreme acidophile in bacterial defense against environmental acid stress.","authors":"Wenbo Hu, Xingyu Huo, Tengfei Ma, Zhigang Li, Tianyou Yang, Hailin Yang, Shoushuai Feng","doi":"10.1007/s00792-024-01368-w","DOIUrl":"https://doi.org/10.1007/s00792-024-01368-w","url":null,"abstract":"<p><p>The cell membrane remodeling mediated by cyclopropane fatty acid synthase (CfaS) plays a crucial role in microbial physiological processes resisting various environmental stressors, including acid. Herein, we found a relatively high proportion (24.8%-28.3%) of cyclopropane fatty acid (CFA) Cy-19:0 in the cell membrane of a newly isolated extreme acidophile, Acidithiobacillus caldus CCTCC AB 2019256, under extreme acid stress. Overexpression of the CfaS encoding gene cfaS2 in Escherichia coli conferred enhanced acid resistance. GC-MS analysis revealed a 3.52-fold increase in the relative proportion of Cy-19:0 in the cell membrane of the overexpression strain compared to the control. Correspondingly, membrane fluidity, permeability and cell surface hydrophobicity were reduced to varying degrees. Additionally, HPLC analysis indicated that the overexpression strain had 1.54-, 1.42-, 1.85-, 1.20- and 1.05-fold higher levels of intracellular glutamic acid, arginine, aspartic acid, methionine and alanine, respectively, compared to the control. Overall, our findings shed light on the role of CfaS derived from extreme acidophile in bacterial defense against environmental acid stress, potentially facilitating its application in the design and development of industrial microbial chassis cells for organic acid production.</p>","PeriodicalId":12302,"journal":{"name":"Extremophiles","volume":"29 1","pages":"1"},"PeriodicalIF":2.6,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142643483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}