Arwa Gabr, Timothy G. Stephens, John R. Reinfelder, Pinky Liau, Victoria Calatrava, Arthur R. Grossman, Debashish Bhattacharya
{"title":"Evidence of a putative CO2 delivery system to the chromatophore in the photosynthetic amoeba Paulinella","authors":"Arwa Gabr, Timothy G. Stephens, John R. Reinfelder, Pinky Liau, Victoria Calatrava, Arthur R. Grossman, Debashish Bhattacharya","doi":"10.1111/1758-2229.13304","DOIUrl":"10.1111/1758-2229.13304","url":null,"abstract":"<p>The photosynthetic amoeba, <i>Paulinella</i> provides a recent (ca. 120 Mya) example of primary plastid endosymbiosis. Given the extensive data demonstrating host lineage-driven endosymbiont integration, we analysed nuclear genome and transcriptome data to investigate mechanisms that may have evolved in <i>Paulinella micropora</i> KR01 (hereinafter, KR01) to maintain photosynthetic function in the novel organelle, the chromatophore. The chromatophore is of α-cyanobacterial provenance and has undergone massive gene loss due to Muller's ratchet, but still retains genes that encode the ancestral α-carboxysome and the shell carbonic anhydrase, two critical components of the biophysical CO<sub>2</sub> concentrating mechanism (CCM) in cyanobacteria. We identified KR01 nuclear genes potentially involved in the CCM that arose via duplication and divergence and are upregulated in response to high light and downregulated under elevated CO<sub>2</sub>. We speculate that these genes may comprise a novel CO<sub>2</sub> delivery system (i.e., a biochemical CCM) to promote the turnover of the RuBisCO carboxylation reaction and counteract photorespiration. We posit that KR01 has an inefficient photorespiratory system that cannot fully recycle the C<sub>2</sub> product of RuBisCO oxygenation back to the Calvin-Benson cycle. Nonetheless, both these systems appear to be sufficient to allow <i>Paulinella</i> to persist in environments dominated by faster-growing phototrophs.</p>","PeriodicalId":163,"journal":{"name":"Environmental Microbiology Reports","volume":"16 3","pages":""},"PeriodicalIF":3.6,"publicationDate":"2024-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11194058/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141454138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Eduardo Pérez-Pazos, Katilyn V. Beidler, Achala Narayanan, Briana H. Beatty, François Maillard, Alexandra Bancos, Katherine A. Heckman, Peter G. Kennedy
{"title":"Fungi rather than bacteria drive early mass loss from fungal necromass regardless of particle size","authors":"Eduardo Pérez-Pazos, Katilyn V. Beidler, Achala Narayanan, Briana H. Beatty, François Maillard, Alexandra Bancos, Katherine A. Heckman, Peter G. Kennedy","doi":"10.1111/1758-2229.13280","DOIUrl":"10.1111/1758-2229.13280","url":null,"abstract":"<p>Microbial necromass is increasingly recognized as an important fast-cycling component of the long-term carbon present in soils. To better understand how fungi and bacteria individually contribute to the decomposition of fungal necromass, three particle sizes (>500, 250–500, and <250 μm) of <i>Hyaloscypha bicolor</i> necromass were incubated in laboratory microcosms inoculated with individual strains of two fungi and two bacteria. Decomposition was assessed after 15 and 28 days via necromass loss, microbial respiration, and changes in necromass pH, water content, and chemistry. To examine how fungal–bacterial interactions impact microbial growth on necromass, single and paired cultures of bacteria and fungi were grown in microplates containing necromass-infused media. Microbial growth was measured after 5 days through quantitative PCR. Regardless of particle size, necromass colonized by fungi had higher mass loss and respiration than both bacteria and uninoculated controls. Fungal colonization increased necromass pH, water content, and altered chemistry, while necromass colonized by bacteria remained mostly unaltered. Bacteria grew significantly more when co-cultured with a fungus, while fungal growth was not significantly affected by bacteria. Collectively, our results suggest that fungi act as key early decomposers of fungal necromass and that bacteria may require the presence of fungi to actively participate in necromass decomposition.</p>","PeriodicalId":163,"journal":{"name":"Environmental Microbiology Reports","volume":"16 3","pages":""},"PeriodicalIF":3.6,"publicationDate":"2024-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11194057/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141454140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jason Bosch, Pedro H. Lebre, Eugene Marais, Gillian Maggs-Kölling, Don A. Cowan
{"title":"Kinetics and pathways of sub-lithic microbial community (hypolithon) development","authors":"Jason Bosch, Pedro H. Lebre, Eugene Marais, Gillian Maggs-Kölling, Don A. Cowan","doi":"10.1111/1758-2229.13290","DOIUrl":"10.1111/1758-2229.13290","url":null,"abstract":"<p>Type I hypolithons are microbial communities dominated by Cyanobacteria. They adhere to the underside of semi-translucent rocks in desert pavements, providing them with a refuge from the harsh abiotic stresses found on the desert soil surface. Despite their crucial role in soil nutrient cycling, our understanding of their growth rates and community development pathways remains limited. This study aimed to quantify the dynamics of hypolithon formation in the pavements of the Namib Desert. We established replicate arrays of sterile rock tiles with varying light transmission in two areas of the Namib Desert, each with different annual precipitation regimes. These were sampled annually over 7 years, and the samples were analysed using eDNA extraction and 16S rRNA gene amplicon sequencing. Our findings revealed that in the zone with higher precipitation, hypolithon formation became evident in semi-translucent rocks 3 years after the arrays were set up. This coincided with a Cyanobacterial ‘bloom’ in the adherent microbial community in the third year. In contrast, no visible hypolithon formation was observed at the array set up in the hyper-arid zone. This study provides the first quantitative evidence of the kinetics of hypolithon development in hot desert environments, suggesting that development rates are strongly influenced by precipitation regimes.</p>","PeriodicalId":163,"journal":{"name":"Environmental Microbiology Reports","volume":"16 3","pages":""},"PeriodicalIF":3.6,"publicationDate":"2024-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11194044/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141454141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lucia Maestre-Carballa, Vicente Navarro-López, Manuel Martinez-Garcia
{"title":"Metagenomic airborne resistome from urban hot spots through the One Health lens","authors":"Lucia Maestre-Carballa, Vicente Navarro-López, Manuel Martinez-Garcia","doi":"10.1111/1758-2229.13306","DOIUrl":"10.1111/1758-2229.13306","url":null,"abstract":"<p>Human activities are a significant contributor to the spread of antibiotic resistance genes (ARGs), which pose a serious threat to human health. These ARGs can be transmitted through various pathways, including air, within the context of One Health. This study used metagenomics to monitor the resistomes in urban air from two critical locations: a wastewater treatment plant and a hospital, both indoor and outdoor. The presence of cell-like structures was confirmed through fluorescence microscopy. The metagenomic analysis revealed a wide variety of ARGs and a high diversity of antibiotic-resistant bacteria in the airborne particles collected. The wastewater treatment plant showed higher relative abundances with 32 ARG hits per Gb and m<sup>3</sup>, followed by the main entrance of the hospital (indoor) with ≈5 ARG hits per Gb and m<sup>3</sup>. The hospital entrance exhibited the highest ARG richness, with a total of 152 different ARGs classified into nine categories of antibiotic resistance. Common commensal and pathogenic bacteria carrying ARGs, such as <i>Moraxella</i>, <i>Staphylococcus</i> and <i>Micrococcus</i>, were detected in the indoor airborne particles of the hospital. Interestingly, no ARGs were shared among all the samples analysed, indicating a highly variable dynamic of airborne resistomes. Furthermore, the study found no ARGs in the airborne viral fractions analysed, suggesting that airborne viruses play a negligible role in the dissemination of ARGs.</p>","PeriodicalId":163,"journal":{"name":"Environmental Microbiology Reports","volume":"16 3","pages":""},"PeriodicalIF":3.6,"publicationDate":"2024-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11194455/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141454142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Katelyn M. Brown, Katelyn B. Barker, Ryan S. Wagner, Christopher S. Ward, Lewis Sitoki, James Njiru, Reuben Omondi, James Achiya, Albert Getabu, R. Michael McKay, George S. Bullerjahn, the NSF-IRES Lake Victoria Research Consortium
{"title":"Bacterial community and cyanotoxin gene distribution of the Winam Gulf, Lake Victoria, Kenya","authors":"Katelyn M. Brown, Katelyn B. Barker, Ryan S. Wagner, Christopher S. Ward, Lewis Sitoki, James Njiru, Reuben Omondi, James Achiya, Albert Getabu, R. Michael McKay, George S. Bullerjahn, the NSF-IRES Lake Victoria Research Consortium","doi":"10.1111/1758-2229.13297","DOIUrl":"10.1111/1758-2229.13297","url":null,"abstract":"<p>The Winam Gulf (Kenya) is frequently impaired by cyanobacterial harmful algal blooms (cHABs) due to inadequate wastewater treatment and excess agricultural nutrient input. While phytoplankton in Lake Victoria have been characterized using morphological criteria, our aim is to identify potential toxin-producing cyanobacteria using molecular approaches. The Gulf was sampled over two successive summer seasons, and 16S and 18S ribosomal RNA gene sequencing was performed. Additionally, key genes involved in production of cyanotoxins were examined by quantitative PCR. Bacterial communities were spatially variable, forming distinct clusters in line with regions of the Gulf. Taxa associated with diazotrophy were dominant near Homa Bay. On the eastern side, samples exhibited elevated <i>cyrA</i> abundances, indicating genetic capability of cylindrospermopsin synthesis. Indeed, near the Nyando River mouth in 2022, <i>cyrA</i> exceeded 10 million copies L<sup>−1</sup> where there were more than 6000 <i>Cylindrospermopsis</i> spp. cells mL<sup>−1</sup>. In contrast, the southwestern region had elevated <i>mcyE</i> gene (microcystin synthesis) detections near Homa Bay where <i>Microcystis</i> and <i>Dolichospermum</i> spp. were observed. These findings show that within a relatively small embayment, composition and toxin synthesis potential of cHABs can vary dramatically. This underscores the need for multifaceted management approaches and frequent cyanotoxin monitoring to reduce human health impacts.</p>","PeriodicalId":163,"journal":{"name":"Environmental Microbiology Reports","volume":"16 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1758-2229.13297","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141416968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Igor S. Pessi, Tom O. Delmont, Jonathan P. Zehr, Jenni Hultman
{"title":"Discovery of Eremiobacterota with nifH homologues in tundra soil","authors":"Igor S. Pessi, Tom O. Delmont, Jonathan P. Zehr, Jenni Hultman","doi":"10.1111/1758-2229.13277","DOIUrl":"10.1111/1758-2229.13277","url":null,"abstract":"<p>We describe the genome of an Eremiobacterota population from tundra soil that contains the minimal set of <i>nif</i> genes needed to fix atmospheric N<sub>2</sub>. This putative diazotroph population, which we name <i>Candidatus</i> Lamibacter sapmiensis, links for the first time Eremiobacterota and N<sub>2</sub> fixation. The integrity of the genome and its <i>nif</i> genes are well supported by both environmental and taxonomic signals. Ca. Lamibacter sapmiensis contains three <i>nifH</i> homologues and the complementary set of <i>nifDKENB</i> genes that are needed to assemble a functional nitrogenase. The putative diazotrophic role of Ca. Lamibacter sapmiensis is supported by the presence of genes that regulate N<sub>2</sub> fixation and other genes involved in downstream processes such as ammonia assimilation. Similar to other Eremiobacterota, Ca. Lamibacter sapmiensis encodes the potential for atmospheric chemosynthesis via CO<sub>2</sub> fixation coupled with H<sub>2</sub> and CO oxidation. Interestingly, the presence of a N<sub>2</sub>O reductase indicates that this population could play a role as a N<sub>2</sub>O sink in tundra soils. Due to the lack of activity data, it remains uncertain if Ca. Lamibacter sapmiensis is able to assemble a functional nitrogenase and participate in N<sub>2</sub> fixation. Confirmation of this ability would be a testament to the great metabolic versatility of Eremiobacterota, which appears to underlie their ecological success in cold and oligotrophic environments.</p>","PeriodicalId":163,"journal":{"name":"Environmental Microbiology Reports","volume":"16 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11180709/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141329851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sandra Åhlén Mulio, Agnieszka Zwolińska, Tomasz Klejdysz, Monika Prus-Frankowska, Anna Michalik, Michał Kolasa, Piotr Łukasik
{"title":"Limited variation in microbial communities across populations of Macrosteles leafhoppers (Hemiptera: Cicadellidae)","authors":"Sandra Åhlén Mulio, Agnieszka Zwolińska, Tomasz Klejdysz, Monika Prus-Frankowska, Anna Michalik, Michał Kolasa, Piotr Łukasik","doi":"10.1111/1758-2229.13279","DOIUrl":"10.1111/1758-2229.13279","url":null,"abstract":"<p>Microbial symbionts play crucial roles in insect biology, yet their diversity, distribution, and temporal dynamics across host populations remain poorly understood. In this study, we investigated the spatio-temporal distribution of bacterial symbionts within the widely distributed and economically significant leafhopper genus <i>Macrosteles</i>, with a focus on <i>Macrosteles laevis</i>. Using host and symbiont marker gene amplicon sequencing, we explored the intricate relationships between these insects and their microbial partners. Our analysis of the cytochrome oxidase subunit I (COI) gene data revealed several intriguing findings. First, there was no strong genetic differentiation across <i>M. laevis</i> populations, suggesting gene flow among them. Second, we observed significant levels of heteroplasmy, indicating the presence of multiple mitochondrial haplotypes within individuals. Third, parasitoid infections were prevalent, highlighting the complex ecological interactions involving leafhoppers. The 16S rRNA data confirmed the universal presence of ancient nutritional endosymbionts—<i>Sulcia</i> and <i>Nasuia</i>—in <i>M. laevis</i>. Additionally, we found a high prevalence of <i>Arsenophonus</i>, another common symbiont. Interestingly, unlike most previously studied species, <i>M. laevis</i> exhibited only occasional cases of infection with known facultative endosymbionts and other bacteria. Notably, there was no significant variation in symbiont prevalence across different populations or among sampling years within the same population. Comparatively, facultative endosymbionts such as <i>Rickettsia</i>, <i>Wolbachia</i>, <i>Cardinium</i> and <i>Lariskella</i> were more common in other <i>Macrosteles</i> species. These findings underscore the importance of considering both host and symbiont dynamics when studying microbial associations. By simultaneously characterizing host and symbiont marker gene amplicons in large insect collections, we gain valuable insights into the intricate interplay between insects and their microbial partners. Understanding these dynamics contributes to our broader comprehension of host–microbe interactions in natural ecosystems.</p>","PeriodicalId":163,"journal":{"name":"Environmental Microbiology Reports","volume":"16 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1758-2229.13279","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141295156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jussi S. Vesamäki, Miikka B. Laine, Riitta Nissinen, Sami J. Taipale
{"title":"Plastic and terrestrial organic matter degradation by the humic lake microbiome continues throughout the seasons","authors":"Jussi S. Vesamäki, Miikka B. Laine, Riitta Nissinen, Sami J. Taipale","doi":"10.1111/1758-2229.13302","DOIUrl":"10.1111/1758-2229.13302","url":null,"abstract":"<p>Boreal freshwaters go through four seasons, however, studies about the decomposition of terrestrial and plastic compounds often focus only on summer. We compared microbial decomposition of <sup>13</sup>C-polyethylene, <sup>13</sup>C-polystyrene, and <sup>13</sup>C-plant litter (<i>Typha latifolia</i>) by determining the biochemical fate of the substrate carbon and identified the microbial decomposer taxa in humic lake waters in four seasons. For the first time, the annual decomposition rate including separated seasonal variation was calculated for microplastics and plant litter in the freshwater system. Polyethylene decomposition was not detected, whereas polystyrene and plant litter were degraded in all seasons. In winter, decomposition rates of polystyrene and plant litter were fivefold and fourfold slower than in summer, respectively. Carbon from each substrate was mainly respired in all seasons. Plant litter was utilized efficiently by various microbial groups, whereas polystyrene decomposition was limited to Alpha- and Gammaproteobacteria. The decomposition was not restricted only to the growth season, highlighting that the decomposition of both labile organic matter and extremely recalcitrant microplastics continues throughout the seasons.</p>","PeriodicalId":163,"journal":{"name":"Environmental Microbiology Reports","volume":"16 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1758-2229.13302","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141295157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Comparative metabolic profiling of the mycelium and fermentation broth of Penicillium restrictum from Peucedanum praeruptorum rhizosphere","authors":"Yuanyuan Wang, Ranran Liao, Haoyu Pan, Xuejun Wang, Xiaoting Wan, Bangxing Han, Cheng Song","doi":"10.1111/1758-2229.13286","DOIUrl":"10.1111/1758-2229.13286","url":null,"abstract":"<p>Microorganisms in the rhizosphere, particularly arbuscular mycorrhiza, have a broad symbiotic relationship with their host plants. One of the major fungi isolated from the rhizosphere of <i>Peucedanum praeruptorum</i> is <i>Penicillium restrictum</i>. The relationship between the metabolites of <i>P. restrictum</i> and the root exudates of <i>P. praeruptorum</i> is being investigated. The accumulation of metabolites in the mycelium and fermentation broth of <i>P. restrictum</i> was analysed over different fermentation periods. Non-targeted metabolomics was used to compare the differences in intracellular and extracellular metabolites over six periods. There were significant differences in the content and types of mycelial metabolites during the incubation. Marmesin, an important intermediate in the biosynthesis of coumarins, was found in the highest amount on the fourth day of incubation. The differential metabolites were screened to obtain 799 intracellular and 468 extracellular differential metabolites. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis showed that the highly enriched extracellular metabolic pathways were alanine, aspartate and glutamate metabolism, glyoxylate and dicarboxylate metabolism, and terpenoid backbone biosynthesis. In addition, the enrichment analysis associated with intracellular and extracellular ATP-binding cassette transporter proteins revealed that some ATP-binding cassette transporters may be involved in the transportation of certain amino acids and carbohydrates. Our results provide some theoretical basis for the regulatory mechanisms between the rhizosphere and the host plant and pave the way for the heterologous production of furanocoumarin.</p>","PeriodicalId":163,"journal":{"name":"Environmental Microbiology Reports","volume":"16 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1758-2229.13286","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141282466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Radwa Moanis, Hannelore Geeraert, Niko Van den Brande, Ulrich Hennecke, Eveline Peeters
{"title":"Paracoccus kondratievae produces poly(3-hydroxybutyrate) under elevated temperature conditions","authors":"Radwa Moanis, Hannelore Geeraert, Niko Van den Brande, Ulrich Hennecke, Eveline Peeters","doi":"10.1111/1758-2229.13260","DOIUrl":"https://doi.org/10.1111/1758-2229.13260","url":null,"abstract":"<p>As part of ongoing efforts to discover novel polyhydroxyalkanoate-producing bacterial species, we embarked on characterizing the thermotolerant species, <i>Paracoccus kondratievae</i>, for biopolymer synthesis. Using traditional chemical and thermal characterization techniques, we found that <i>P. kondratievae</i> accumulates poly(3-hydroxybutyrate) (PHB), reaching up to 46.8% of the cell's dry weight after a 24-h incubation at 42°C. Although <i>P. kondratievae</i> is phylogenetically related to the prototypical polyhydroxyalkanoate producer, <i>Paracoccus denitrificans</i>, we observed significant differences in the PHB production dynamics between these two <i>Paracoccus</i> species. Notably, <i>P. kondratievae</i> can grow and produce PHB at elevated temperatures ranging from 42 to 47°C. Furthermore, <i>P. kondratievae</i> reaches its peak PHB content during the early stationary growth phase, specifically after 24 h of growth in a flask culture. This is then followed by a decline in the later stages of the stationary growth phase. The depolymerization observed in this growth phase is facilitated by the abundant presence of the PhaZ depolymerase enzyme associated with PHB granules. We observed the highest PHB levels when the cells were cultivated in a medium with glycerol as the sole carbon source and a carbon-to-nitrogen ratio of 10. Finally, we found that PHB production is induced as an osmotic stress response, similar to other polyhydroxyalkanoate-producing species.</p>","PeriodicalId":163,"journal":{"name":"Environmental Microbiology Reports","volume":"16 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1758-2229.13260","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141251464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}