Systematic and applied microbiology最新文献

{"title":"Halosimplex amylolyticum sp. nov., Halosimplex halobium sp. nov., Halosimplex marinum sp. nov., Halosimplex rarum sp. nov., Halovenus amylolytica sp. nov., Halovenus halobia sp. nov., and Halovenus marina sp. nov., halophilic archaea isolated from a marine tidal flat, a marine solar saltern, three coarse sea salts, and two saline lakes","authors":"Ya-Ling Mao,&nbsp;Shun Tan,&nbsp;Bei-Bei Wang,&nbsp;Xiao-Yan Yang,&nbsp;Jing Hou,&nbsp;Heng-Lin Cui","doi":"10.1016/j.syapm.2025.126626","DOIUrl":"10.1016/j.syapm.2025.126626","url":null,"abstract":"<div><div>Seven novel halophilic archaeal strains DYHT-AS-1^T, GDY60^T, TS25^T, XH63^T, SHR40^T, SYNS179^T, and ZY30^T were isolated from tidal flat, saline lakes, marine solar saltern and coarse sea salts from different regions of China. Metagenomic and amplicon analyses indicated that the abundance of these seven strains in respective habitats was low. Phylogenetic and comparative genomic analyses indicated that strains DYHT-AS-1^T, GDY60^T, TS25^T, and XH63^T formed a tight cluster with <em>Halosimplex</em> species, exhibiting high 16S rRNA gene sequence similarity (90.4–99.4 %). The ANI, dDDH, and AAI values among these four strains and current <em>Halosimplex</em> species were 80.8–92.3 %, 24.5–53.3 %, and 77.8–91.5 %, respectively. Strains SHR40^T, SYNS179^T, and ZY30^T were related to <em>Halovenus</em> species, with 16S rRNA gene sequence similarities ranging from 88.8 % to 98.4 %. The ANI, dDDH, and AAI values among these three strains and current <em>Halovenus</em> species were 69.9–77.8 %, 19.4–21.5 %, and 62.1–78.1 %, respectively. These values are significantly lower than the thresholds for species demarcation. The optimal growth conditions for these seven strains in terms of NaCl, MgCl₂, temperature, and pH were 3.1–3.4 M, 0.05–0.5 M, 35–40 °C, and 6.5–7.5, respectively. According to phenotypic differences in nutrition, biochemical activity, and antibiotic sensitivity, these seven strains can be distinguished from their related species. Based on the above results, strains DYHT-AS-1^T, GDY60^T, TS25^T, and XH63^T represent four new species of the genus <em>Halosimplex</em>, and strains SHR40^T, SYNS179^T, and ZY30^T represent three novel species of the genus <em>Halovenus</em>.</div></div>","PeriodicalId":22124,"journal":{"name":"Systematic and applied microbiology","volume":"48 4","pages":"Article 126626"},"PeriodicalIF":3.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144222370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Classification of MAGs associated with trace gas metabolism in volcanic soils named following SeqCode rules","authors":"Shamik Roy ,&nbsp;Gary M. King ,&nbsp;Marcela Hernández","doi":"10.1016/j.syapm.2025.126622","DOIUrl":"10.1016/j.syapm.2025.126622","url":null,"abstract":"<div><div>Trace gas metabolism is important for nutrient flow in all ecosystems, particularly volcanic ecosystems. Microbes in volcanic ecosystems are among the early colonisers and can play key roles in ecological succession. Here, we describe the taxonomic and functional characteristics of two new metagenome-assembled genomes (MAGs), one belonging to <em>Bacteria</em> (MAG_1957-2.1) and one to <em>Archaea</em> (MAG_C2-3), retrieved from soils in volcanoes located in Chile (Llaima) and the USA (Kilauea), respectively. MAG_1957-2.1 has a genome size of 6.36<!--> <!-->Mb with 96.21 % completeness. MAG_C2-3 has a genome size of 3.02<!--> <!-->Mb with 97.57 % completeness. Phylogenetic analyses of the bacterial MAGs placed MAG_1957-2.1 in the class <em>Ktedonobacteria</em>, while the archaeal MAG_C2-3 was placed in the class <em>Nitrososphaeria</em>. Functional characterisation for potential trace gas metabolism showed that MAG_1957-2.1 contains a <em>coxL</em> gene encoding the large subunit of form I carbon monoxide dehydrogenase (CoxL), which is associated with the oxidation of carbon monoxide (CO). It also contains the form I <em>cox</em> gene cluster with a <em>coxMSL</em> arrangement. On the other hand, MAG_C2-3 contains gene subunit A (<em>amoA</em>) as well as subunit B (<em>amoB</em>), which encode for ammonia monooxygenase, the enzyme that catalyses the oxidation of ammonia. Based on the sequence characteristics and phylogenomic analyses we propose the names <em>Paraktedonobacter carboxidivorans sp.</em> nov for MAG_1957-2.1 and <em>Nitrososphaera maunauluensis sp.</em> nov for MAG_C2-3. The names are proposed following the rules of the published Code of Nomenclature of Prokaryotes Described from Sequence Data (SeqCode).</div></div>","PeriodicalId":22124,"journal":{"name":"Systematic and applied microbiology","volume":"48 4","pages":"Article 126622"},"PeriodicalIF":3.3,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144230868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnetovirga frankeli gen. Nov., sp. nov., a magnetotactic bacterium isolated from the Salton Sea, California, that represents a novel lineage in the Gammaprotoeobacteria","authors":"Mila Sirinelli-Kojadinovic ,&nbsp;Elsa C.A. Turrini ,&nbsp;Emma Ropion ,&nbsp;Béatrice Alonso ,&nbsp;Marine Bergot ,&nbsp;Emilie Gachon ,&nbsp;Philippe Ortet ,&nbsp;Paul E.D. Soto-Rodriguez ,&nbsp;Caroline L. Monteil ,&nbsp;Christopher T. Lefevre","doi":"10.1016/j.syapm.2025.126621","DOIUrl":"10.1016/j.syapm.2025.126621","url":null,"abstract":"<div><div>A magnetotactic bacterium, designated strain SS-5^T, was isolated from the Salton Sea, a highly saline lake in California, USA, and cultivated in axenic culture. The Gram-negative cells of strain SS-5^T are relatively small and rod-shaped and possess a single polar flagellum (monotrichous). This strain is a magnetotactic bacterium producing magnetite nanocrystals aligned in one chain per cell. Strain SS-5^T is a microaerophile that grows chemolithoautotrophically while reducing oxygen as a terminal electron acceptor. Optimal growth occurred at pH 7.0–7.3 and 28–36 °C with thiosulfate used as an electron donor and sodium bicarbonate as a carbon source. Based on its genome sequence, the G + C content is 61.6 %. Phylogenomic and phylogenetic analyses indicate that strain SS-5^T belongs to the <em>Sedimenticolaceae</em> family within the <em>Gammaproteobacteria</em> class. Based on average amino acid identity, strain SS-5^T can be considered as a novel species of a new genus, for which the name <em>Magnetovirga frankeli</em> is proposed. The type strain of <em>M. frankeli</em> is SS-5^T (=DSM 116211^T = JCM 39467^T).</div></div>","PeriodicalId":22124,"journal":{"name":"Systematic and applied microbiology","volume":"48 4","pages":"Article 126621"},"PeriodicalIF":3.3,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144154697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Macrococcus capreoli sp. nov., a new fosfomycin resistant species isolated from feces and nasal swabs of deer","authors":"Carolin J. Schiffer ,&nbsp;Matthias A. Ehrmann","doi":"10.1016/j.syapm.2025.126620","DOIUrl":"10.1016/j.syapm.2025.126620","url":null,"abstract":"<div><div>Five strains of Gram-stain-positive, non-motile, and coccoid-shaped bacteria, designated as TMW 2.2395^T, TMW 2.2628, TMW 2.2670, TMW 2.2756 and TMW 2.2757 were isolated from feces and nasal mucosa of wild living roe deer (<em>Capreolus capreolus</em>) and red deer (<em>Cervus elaphus</em>), respectively. The isolates share identical 16S rRNA gene sequences and are classified within the genus <em>Macrococcus</em> based on 16S and MALDI-TOF MS analyses. Phylogenetic analysis revealed that average nucleotide identity (ANI) values were below the accepted thresholds for prokaryotic species delineation, with the type strains of <em>M. goetzii</em>, <em>M. bohemicu</em><em>s</em> and <em>M. epidermidis</em> showing the highest relatedness values (79.59 %, 79.30 % and 79.52 %, respectively). Digital DNA–DNA hybridization (dDDH) values were below 23 % confirming that all five strains belong to a new species within the genus <em>Macrococcus</em>. All strains were catalase and oxidase positive, grew optimally at 37 °C and pH 7.0, but demonstrated considerably lower salt tolerance (&lt; 7.5 % <em>w</em><em>/</em><em>v</em> nit iterativ) compared to other species in the genus. Moreover, the data of this study suggests that members of this new species possess an intrinsic resistance to fosfomycin, putatively mediated by a <em>fosB</em> homologue. The genomes range from 2.4 and 2.5 Mb in size, with a G+C content of 34.8 to 35.1 %. The primary respiratory quinone of the type strain TMW 2.2395^T is Menaquinone 6 (MK-6, 98.6 %), the cell wall peptidoglycan type is A3α L-Lys-Gly₃-L-Ser and the major fatty acids are C_14:0, C_16:0 and C_18:0. Phylogenetic, phenotypic and chemotaxonomic data collectively suggest that these strains represent a novel species of the genus <em>Macrococcus</em>, for which the name <em>Macrococcus capreoli</em> sp. nov. is proposed. The type strain is TMW 2.2395^T = DSM 113939^T = LMG 32618^T.</div></div>","PeriodicalId":22124,"journal":{"name":"Systematic and applied microbiology","volume":"48 4","pages":"Article 126620"},"PeriodicalIF":3.3,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144168666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unveiling the hidden microbiome: a microbiological exploration of untouched burial crypts in Krakow, Poland","authors":"Patrycja Tarnawska ,&nbsp;Aleksandra Burkowska-But ,&nbsp;Maria Swiontek Brzezińska ,&nbsp;Anna Drążkowska ,&nbsp;Adriana Osińska ,&nbsp;Maciej Walczak","doi":"10.1016/j.syapm.2025.126618","DOIUrl":"10.1016/j.syapm.2025.126618","url":null,"abstract":"<div><div>Cultural heritage objects provide valuable historical information, but can also harbour biological threats. Still, little is said about the potential risks that may await unaware researchers, conservators, and archaeologists. Our work discusses the study results from the crypts in Krakow, which were opened for the first time. The human and coffin remains were examined. The number of actinomycetes, other mesophilic bacteria, bacterial spores, and xerophilic and non-xerophilic fungi was determined. In general, a low number of microbes was observed. However, scanning electron microscope (SEM) images showed many bacterial conglomerates and confirmed that microbial activity affected the fibres covering cadavers in the crypts. The most abundant were mesophilic bacteria, followed by bacterial spores and actinomycetes. They reached up to 10⁷ CFU/g in fabric remains, 5.2 × 10⁶ CFU/g in burial remains, and 1.6 × 10⁶ CFU/g found under the coffin, and above 7.5 × 10⁵ CFU/g for xerophilic and non-xerophilic fungi. NGS (Next-Generation Sequencing) results suggested that the low presence of microorganisms may be due to the dominance of unculturable or long-growing bacteria belonging to <em>Mycobacterium</em>, such as <em>M. coloregonium</em>, <em>M. arupense</em>, and <em>M. pinnipedii.</em> Moreover, other obligatory/non-obligatory pathogens, <em>Bacteroides fragilis, Clostridium botulinum, Coxiella burnetii</em>, <em>Clostridium tetani</em>, <em>Corynebacterium diphtheriae</em>, <em>Enterobacter cloacae</em>, <em>Escherichia coli</em>, <em>Legionella pneumophila</em>, <em>Mycobacterium leprae</em>, <em>Rhodococcus equi</em>, and <em>Staphylococcus aureus</em> have been recorded in examined samples, with the dominance in bone samples. Results indicate the risk of dangerous pathogens present in historical objects, the impact on health may be severe, and the need to use personal protective equipment and proper measures to control the physical conditions of crypts.</div></div>","PeriodicalId":22124,"journal":{"name":"Systematic and applied microbiology","volume":"48 4","pages":"Article 126618"},"PeriodicalIF":3.3,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144168667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rhizobium binxianense sp. nov. and Rhizobium mulingense sp. nov., isolated from nodules of Phaseolus vulgaris in Heilongjiang Province of China","authors":"Yuxi Liu ,&nbsp;Lili Liu ,&nbsp;Ziqi Wang ,&nbsp;Xiaoqian Huang ,&nbsp;Yuxin Dong ,&nbsp;Dong Hu ,&nbsp;Chuntao Gu ,&nbsp;En Tao Wang ,&nbsp;Hao Wang","doi":"10.1016/j.syapm.2025.126619","DOIUrl":"10.1016/j.syapm.2025.126619","url":null,"abstract":"<div><div>Rhizobial isolates from <em>Phaseolus vulgaris</em> (common bean) grown in Heilongjiang Province were grouped into two clusters based upon the phylogenies of 16S rRNA and <em>recA-atpD</em> genes representing by BJ04^T, MJ22, MJ37, BC56, MC62 and MC63^T, MJ21, MJ31, respectively. The phylogenetic analysis of whole genomes further revealed that BJ04^T, MJ22, MJ37, BC56 and MC62 formed a cluster neighbored <em>Rhizobium chutanense</em> C5^T, while MC63^T, MJ21 and MJ31 formed a cluster most related with <em>Rhizobium croatiense</em> 13T^T. The whole genome average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between the strains BJ04^T and <em>R. chutanense</em> C5^T and between MC63^T and <em>R. croatiense</em> 13T^T were lower than the species thresholds 95 % and 70 %, respectively. While the G + C content of the whole genome of the novel strains were 61.16–61.56 %, within the allowable GC content range of the <em>Rhizobium</em> genus (57–66 %). These results, combined with chemical classification and phenotype analysis, supported that BJ04^T and MC63^T represented two novel species and the names <em>Rhizobium binxianense</em> sp. nov. and <em>Rhizobium mulingense</em> sp. nov. were described for them. BJ04^T (=CCTCC AB 2022367^T, = JCM 35885^T) and MC63^T (=CCTCC AB 2024025^T, = JCM 36652^T) were designed as the type strains, respectively for these two novel species.</div></div>","PeriodicalId":22124,"journal":{"name":"Systematic and applied microbiology","volume":"48 4","pages":"Article 126619"},"PeriodicalIF":3.3,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144137847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"N-glyceroyl alkylamine phosphoglycolipids dominate the lipidome of several Bacillota bacteria","authors":"Nicole J. Bale ,&nbsp;Michel Koenen ,&nbsp;Su Ding ,&nbsp;Jaap S. Sinninghe Damsté","doi":"10.1016/j.syapm.2025.126609","DOIUrl":"10.1016/j.syapm.2025.126609","url":null,"abstract":"<div><div>Elucidation of the membrane lipid composition of bacteria can help to better understand how bacterial cells interact with their surroundings, adapt to environmental stress, and resist antimicrobial agents. Here we describe for the first time the detection of a wide array of N-glyceroyl alkylamine phosphoglycolipids (NGAPs) in a range of <em>Bacillota</em> bacteria (formerly <em>Firmicutes</em>). <em>Bacillota</em> includes a diverse range of bacteria that are typically highly resistant to harsh conditions such as heat, radiation, and pH, allowing the bacteria to survive in unfavorable environments. In 9 out 18 investigated strains of <em>Bacillota</em>, spread across 5 orders (<em>Thermoanaerobacterales, Thermosediminibacterales, Eubacteriales, Halanaerobiales</em>, and <em>Sulfobacillia</em>) mild acid hydrolysis released N-glyceroyl alkylamines (NGAs), which were detectable by gas chromatography–mass spectrometry (GC–MS) during routine fatty acid analysis. One strain, <em>Moorella thermoacetica</em> was found to produce long-chain NGAs (C₃₀-C₃₂), which are postulated to have <em>iso</em>diabolic acid-like structures. A wide variety of intact polar NGAPs were identified using ultra-high pressure liquid chromatography high resolution multi-stage mass spectrometry (UHPLC-HRMSⁿ). These include many previously undescribed lipids with a variety of sugar moieties and glycerol-bound core lipid moieties, including ether-bound components and alkyl 1,2-diols. The NGAPs constituted the majority of the intact polar lipid composition of these strains and presumably contribute to their tough cell membranes. The presence of NGAs in <em>Bacillota</em> appears to be associated with thermophilia. Both the hydrolysis-derived NGAs and intact polar NGAPs have potential to be biomarkers for extremophilic and, in particular, thermophilic bacteria.</div></div>","PeriodicalId":22124,"journal":{"name":"Systematic and applied microbiology","volume":"48 4","pages":"Article 126609"},"PeriodicalIF":3.3,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143918523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to: “Flavobacterium plantiphilum sp. nov., Flavobacterium rhizophilum sp. nov., Flavobacterium rhizosphaerae sp. nov., Chryseobacterium terrae sp. nov., and Sphingomonas plantiphila sp. nov. isolated from salty soil showing plant growth promoting potential” [Systematic and Applied Microbiology 48 (2025) 126588]","authors":"Peter Kämpfer ,&nbsp;André Lipski ,&nbsp;Kathy S. Lawrence ,&nbsp;Walker R. Olive ,&nbsp;Molli M. Newman ,&nbsp;John A. McInroy ,&nbsp;Tomeu Viver","doi":"10.1016/j.syapm.2025.126603","DOIUrl":"10.1016/j.syapm.2025.126603","url":null,"abstract":"","PeriodicalId":22124,"journal":{"name":"Systematic and applied microbiology","volume":"48 3","pages":"Article 126603"},"PeriodicalIF":3.3,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143671054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Erratum to “Characterization of two novel species of the genusBifidobacterium: Bifidobacterium saimiriisciurei sp. nov. and Bifidobacterium platyrrhinorum sp. nov.” [Syst. Appl. Microbiol. 43 (2020) 126111]","authors":"Monica Modesto ,&nbsp;Maria Satti ,&nbsp;Koichi Watanabe ,&nbsp;Donatella Scarafile ,&nbsp;Chien-Hsun Huang ,&nbsp;Jong-Shian Liou ,&nbsp;Tomohiko Tamura ,&nbsp;Satomi Saito ,&nbsp;Mizuki Watanabe ,&nbsp;Koji Mori ,&nbsp;Lina Huang ,&nbsp;Camillo Sandri ,&nbsp;Caterina Spiezio ,&nbsp;Masanori Arita ,&nbsp;Paola Mattarelli","doi":"10.1016/j.syapm.2025.126601","DOIUrl":"10.1016/j.syapm.2025.126601","url":null,"abstract":"","PeriodicalId":22124,"journal":{"name":"Systematic and applied microbiology","volume":"48 3","pages":"Article 126601"},"PeriodicalIF":3.3,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143630706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Natronomicrosphaera hydrolytica, gen. nov., sp. nov., a first representative of the phylum Planctomycetota from soda lakes","authors":"Dimitry Y. Sorokin ,&nbsp;Alexander Y. Merkel ,&nbsp;Nicole J. Bale ,&nbsp;Michel Koenen ,&nbsp;Jaap S. Sinninghe Damsté ,&nbsp;Laura Marturano ,&nbsp;Enzo Messina ,&nbsp;Violetta La Cono ,&nbsp;Michail M. Yakimov","doi":"10.1016/j.syapm.2025.126608","DOIUrl":"10.1016/j.syapm.2025.126608","url":null,"abstract":"<div><div>Despite intensive microbiological characterization of soda lake microbial communities, no culturable representatives from the phylum <em>Planctomycetota</em> have been isolated from these haloalkaline habitats. In the context of studying polysaccharide utilization by soda lake microbial communities, we used polysaccharide hyaluronic acid as enrichment substrate at aerobic, moderate haloalkaline conditions (1 M total Na⁺, pH 9.5). This resulted in a selective enrichment and isolation in pure culture of a bacterial strain AB-hyl4 belonging to <em>Planctomycetota</em>. The cells are tiny motile cocci growing in large aggregates, with the Gram-negative type of ultrastructure and producing a yellow pigment. This obligate aerobic saccharolytic heterotroph has an extremely narrow growth substrate range including, besides hyaluronic acid, melezitose and glycerol. The membrane lipids consist of phosphatidylcholine and two types of neutral lipids, including hopanoids and monounsaturated C17 and C19 hydrocarbons. Phylogenomic analysis placed the isolate into the family <em>Phycisphaeraceae</em>, class <em>Phycisphaerae,</em> as a new genus-level lineage. Its genome contained a gene encoding a polysaccharide lyase from the PL8 family which is probably responsible for the degradation of hyaluronic acid to a dimer, followed by its transport and hydrolysis into monomers in periplasm and final glycolytic degradation in cytoplasm. On the basis of distinct phenotypic and genomic properties, strain AB-hyl4^T (DSM 117794 = UQM 41914) is proposed to be classified as <em>Natronomicrosphaera hydrolytica</em> gen. nov., sp. nov.</div></div>","PeriodicalId":22124,"journal":{"name":"Systematic and applied microbiology","volume":"48 3","pages":"Article 126608"},"PeriodicalIF":3.3,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143902308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}