Microbiology-Sgm最新文献

{"title":"An abundance of <i>aliC</i> and <i>aliD</i> genes were identified in saliva using a novel multiplex qPCR to characterize group II non-encapsulated pneumococci with improved specificity.","authors":"Claire S Laxton, Femke L Toekiran, Tzu-Yi Lin, Beta D Lomeda, Maikel S Hislop, Lance Keller, Orchid M Allicock, Anne L Wyllie","doi":"10.1099/mic.0.001555","DOIUrl":"https://doi.org/10.1099/mic.0.001555","url":null,"abstract":"<p><p>Pneumococcal surveillance studies are reporting increasing prevalence of non-encapsulated pneumococci (NESp). NESp are an important reservoir for genetic exchange among streptococci, including for antimicrobial resistance, and are increasingly implicated in disease. Disease-associated NESp commonly carries the virulence genes <i>pspK</i>, or <i>aliC</i> and <i>aliD</i> in their <i>cps</i> locus instead of capsule genes. While molecular methods targeting the cps region are widely used for serotyping encapsulated strains, there are few assays available for the classification of NESp, meaning it is not widely undertaken. Therefore, we exploited these genes as targets for a novel qPCR assay for detecting and classifying NESp strains with improved efficiency and specificity. We conducted bioinformatic analysis on sequences from 402 NESp and 45 other mitis-group streptococci and developed a multiplex-qPCR, targeting <i>pspK</i>, <i>aliD</i> and two regions of <i>aliC</i>. The assay was validated using 16 previously identified NESp isolates. We then applied the assay to DNA extracted from culture-enriched saliva and isolated and characterized suspected NESp colonies, with confirmation by whole genome sequencing. Bioinformatic analyses demonstrated that previously published primers for <i>aliC</i> and <i>aliD</i> had low pneumococcal specificity but indicated that targeting two regions of <i>aliC</i> would improve species specificity, without compromising sensitivity. Our novel multiplex assay accurately typed all isolates. When screening saliva, we found a high prevalence of <i>aliC</i> and <i>aliD</i>, even in samples negative for pneumococcal genes <i>lytA</i> and <i>piaB</i>. Isolated colonies which were <i>aliC</i> and <i>aliD</i> positive could be differentiated as non-pneumococcal streptococci using our assay. Our multiplex-qPCR assay can be used to efficiently screen even highly polymicrobial samples, such as saliva, for NESp genes, to detect and differentiate potentially pathogenic NESp clades from closely related mitis-group streptococci. This will allow for a better understanding of the true prevalence of NESp and its impact on pneumococcal carriage and disease.</p>","PeriodicalId":49819,"journal":{"name":"Microbiology-Sgm","volume":"171 4","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144054742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deletion of <i>fbiC</i> in <i>Streptomyces venezuelae</i> removes autofluorescence in the excitation-emission range of cyan fluorescent protein.","authors":"Parminder Singh Mavi, Klas Flärdh","doi":"10.1099/mic.0.001552","DOIUrl":"https://doi.org/10.1099/mic.0.001552","url":null,"abstract":"<p><p>Autofluorescence poses an impediment to fluorescence microscopy of biological samples. In the Gram-positive, soil-dwelling bacteria of the genus <i>Streptomyces</i>, sources of autofluorescence have not been examined systematically to date. Here, we show that the model organism for the genus, <i>Streptomyces venezuelae</i>, shows autofluorescence in two of the commonly used fluorescence channels for visualizing cyan and green/yellow fluorescent proteins. We identify the source of autofluorescence in the cyan fluorescence channel as redox cofactor factor 420 (F₄₂₀) and target its synthesis to remove it. By deleting the <i>vnz15170</i> (<i>fbiC</i>) gene, which is a key biosynthetic gene for the production of F₄₂₀, we were able to create an autofluorescence-free strain in the cyan range of fluorescence excitation-emission. We demonstrate the usefulness of this strain by imaging the mTurquoise-tagged polar growth-related protein DivIVA and the cell division-related protein FtsZ in the <i>fbiC</i> deletion background. Using live-cell imaging to follow the dynamics of DivIVA and FtsZ, we demonstrate an improved signal-to-noise ratio in the mutant strain. We show that this strain can be a suitable tool for visualizing the localization of proteins in <i>Streptomyces</i> spp. and can facilitate the utilization of multi-colour imaging and fluorescence resonance energy transfer-based imaging.</p>","PeriodicalId":49819,"journal":{"name":"Microbiology-Sgm","volume":"171 4","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144051484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Disruption of <i>Pseudomonas aeruginosa</i> quorum sensing influences biofilm formation without affecting antibiotic tolerance.","authors":"Elvina Smith, Andrew Matthews, Edze R Westra, Rafael Custodio","doi":"10.1099/mic.0.001557","DOIUrl":"https://doi.org/10.1099/mic.0.001557","url":null,"abstract":"<p><p>The opportunistic bacterial pathogen <i>Pseudomonas aeruginosa</i> is a leading cause of antimicrobial resistance-related deaths, and novel antimicrobial therapies are urgently required. <i>P. aeruginosa</i> infections are difficult to treat due to the bacterium's propensity to form biofilms, whereby cells aggregate to form a cooperative, protective structure. Autolysis, the self-killing of bacterial cells, and the bacterial cell-to-cell communication system, quorum sensing (QS), play essential roles in biofilm formation. Strains of <i>P. aeruginosa</i> that have lost the <i>lasI/R</i> QS system commonly develop in patients, and previous studies have characterized distinctive autolysis phenotypes in these strains. Yet, the underlying causes and implications of these autolysis phenotypes remain unknown. This study confirmed these autolysis phenotypes in the PA14 QS mutant strains, Δ<i>lasI</i> and Δ<i>lasR</i>, and investigated the consequences of QS loss and associated autolysis on biofilm formation and antibiotic susceptibility. QS mutants exhibited delayed biofilm formation but ultimately surpassed the wild-type (WT) in biofilm mass. However, the larger biofilm mass of the QS mutants was not reflected in higher live-cell numbers, indicating an altered biofilm structure. Nevertheless, QS mutant biofilms were not more susceptible to antibiotics than the WT. Artificial supplementation of Δ<i>lasI</i> with a QS signal molecule (autoinducer) restored the strain's QS system without the associated costs of QS, enabling Δ<i>lasI</i> to achieve higher pre-treatment and post-treatment live-cell numbers. Overall, the lack of QS functioning was not detrimental to biofilm antibiotic tolerance, though the artificial disruption of QS may reduce the advantages of QS mutants within <i>in vivo</i> mixed-strain populations. Much remains to be understood regarding the regulation and induction of the autolysis phenotypes observed in these strains, and future research to fully elucidate the control and consequences of autolysis may offer potential for novel antimicrobial therapies.</p>","PeriodicalId":49819,"journal":{"name":"Microbiology-Sgm","volume":"171 4","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12032407/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143990318","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":"Transcription factors DksA and PsrA are synergistic contributors to <i>Legionella pneumophila</i> virulence in <i>Acanthamoeba castellanii</i> protozoa.","authors":"Christopher I Graham, Andrew J Gierys, Teassa L MacMartin, Tiffany V Penner, Jordan C Beck, Gerd Prehna, Teresa R de Kievit, Ann Karen C Brassinga","doi":"10.1099/mic.0.001551","DOIUrl":"https://doi.org/10.1099/mic.0.001551","url":null,"abstract":"<p><p>The environmental bacterium <i>Legionella pneumophila</i>, an intracellular parasite of free-living freshwater protozoa as well as an opportunistic human pathogen, has a biphasic lifestyle. The switch from the vegetative replicative form to the environmentally resilient transmissive phase form is governed by a complex stringent response-based regulatory network that includes RNA polymerase co-factor DksA. Here, we report that, through a dysfunctional DksA mutation (DksA1), a synergistic interplay was discovered between DksA and transcription regulator PsrA using the <i>Acanthamoeba castellanii</i> protozoan infection model. Surprisingly, <i>in trans</i> expression of PsrA partially rescued the growth defect of a <i>dksA1</i> strain. Whilst <i>in trans</i> expression of DksA expectantly could fully rescue the growth defect of the <i>dksA1</i> strain, it could also surprisingly rescue the growth defect of a Δ<i>psrA</i> strain. Conversely, the severe intracellular growth defect of a Δ<i>dksA</i> strain could be rescued by <i>in trans</i> expression of DksA and DksA1, but not PsrA. <i>In vitro</i> phenotypic assays show that either DksA or DksA1 was required for extended culturability of bacterial cells, but normal cell morphology and pigmentation required DksA only. Comparative structural modelling predicts that the DksA1 mutation affects the coordination of Mg²⁺ into the active site of RNAP, compromising transcription efficiency. Taken together, we propose that PsrA transcriptionally assists DksA in the expression of select transmissive phase traits. Additionally, <i>in vitro</i> evidence suggests that the long-chain fatty acid metabolic response is mediated by PsrA together with DksA, inferring a novel regulatory link to the stringent response pathway.</p>","PeriodicalId":49819,"journal":{"name":"Microbiology-Sgm","volume":"171 4","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143990323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Co-purification of the GroEL chaperone during outer membrane vesicle purification: insights from <i>Aeromonas salmonicida</i> subsp. <i>salmonicida</i>.","authors":"Maude F Paquet, Steve J Charette","doi":"10.1099/mic.0.001558","DOIUrl":"https://doi.org/10.1099/mic.0.001558","url":null,"abstract":"<p><p>Outer membrane vesicles (OMVs) are naturally produced by Gram-negative bacteria and originate from their outer membrane. They can be extracted using ultracentrifugation or ultrafiltration using concentration columns, followed by purification with a density gradient. However, these methods may co-purify contaminants with similar physical properties. Several studies have identified GroEL, a chaperonin, as a major protein in OMV preparations. Using <i>Aeromonas salmonicida</i> subsp. <i>salmonicida</i> as a model, we detected GroEL by mass spectrometry and observed it in transmission electron microscopy images as separate from OMVs. As a cytoplasmic protein complex, GroEL is more likely a contaminant resulting from bacterial lysis during growth rather than an intrinsic OMV component. The model <i>A. salmonicida</i> subsp. <i>salmonicida</i> proved valuable in reaching this conclusion because it produces high levels of extracellular GroEL and low amounts of OMVs. This study emphasizes the need for caution when interpreting the presence of GroEL in OMV preparations and highlights the importance of rigorous purification methods to ensure OMV purity.</p>","PeriodicalId":49819,"journal":{"name":"Microbiology-Sgm","volume":"171 4","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12038026/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144054743","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":"Genome-wide high-throughput transposon mutagenesis unveils key factors for acidic pH adaptation of <i>Corynebacterium diphtheriae</i>.","authors":"Camila Azevedo Antunes, Emily C A Goodall, Ian R Henderson, David Wild, Alexander Mehltretter, Philipp Ott, Markus Hölzl, Lisa Ott, Gerald Seidel, Andreas Burkovski","doi":"10.1099/mic.0.001554","DOIUrl":"https://doi.org/10.1099/mic.0.001554","url":null,"abstract":"<p><p><i>Corynebacterium diphtheriae,</i> a notable pathogen responsible for the life-threatening disease diphtheria, encounters harsh intracellular environments within the host, particularly within macrophages where acidic conditions prevail. To elucidate the genetic and molecular mechanisms underlying its acid stress response, we employed a Transposon Directed Insertion-site Sequencing approach. This comprehensive study identified crucial genes and pathways facilitating <i>C. diphtheriae</i>'s survival at low pH. In subsequent experiments, the Ktr potassium transport system was identified as a putative key factor for maintaining pH homeostasis and growth under acidic stress. A <i>ktrBA</i> deletion strain exhibited significantly reduced growth at pH 5, which could be restored by <i>ktrBA</i> expression in <i>trans</i>. The deletion strain showed unchanged uptake and survival in macrophages compared to the wild-type, indicating that the Ktr system is not crucial for the survival of <i>C. diphtheriae</i> in phagocytes. These findings advance our understanding of <i>C. diphtheriae</i>'s pathophysiology, further delineating the intricate survival strategies of <i>C. diphtheriae</i> in hostile environments.</p>","PeriodicalId":49819,"journal":{"name":"Microbiology-Sgm","volume":"171 4","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12022263/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144062701","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":"Microbe Profile: <i>Streptomyces venezuelae -</i> a model species to study morphology and differentiation in filamentous bacteria.","authors":"Max L Jordan, Susan Schlimpert","doi":"10.1099/mic.0.001541","DOIUrl":"10.1099/mic.0.001541","url":null,"abstract":"<p><p><i>Streptomyces</i> bacteria are renowned for their multicellular lifestyle and production of bioactive molecules (natural products) with important applications in medicine, agriculture and industry. Studies of several <i>Streptomyces</i> species have provided a foundational understanding of their biology and metabolism. However, investigating the spatiotemporal processes governing the morphogenesis and development of these remarkable bacteria has been technically challenging due to their complex life cycle. The adoption of <i>Streptomyces venezuelae</i> as a new experimental model species has overcome these limitations and opened the door to fully explore the regulation and cell biology of <i>Streptomyces</i> development. A key advantage of <i>S. venezuelae</i> is its ability to complete its entire life cycle in liquid culture, facilitating the effective use of genome-wide analysis techniques and advanced cell biology approaches. This has provided significant new insights into the regulatory networks and molecular mechanisms underlying <i>Streptomyces</i> growth, division, developmental transitions and genome organization.</p>","PeriodicalId":49819,"journal":{"name":"Microbiology-Sgm","volume":"171 3","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11906614/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143626547","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":"Glucose alters the evolutionary response to gentamicin in uropathogenic <i>Escherichia coli</i>.","authors":"Shalini Choudhary, Jacob A Smith, Alan McNally, Rebecca J Hall","doi":"10.1099/mic.0.001548","DOIUrl":"10.1099/mic.0.001548","url":null,"abstract":"<p><p>Urinary tract infections (UTI) are a major health and economic concern. Uropathogenic <i>Escherichia coli</i> (UPEC) are the leading cause of UTI, and antibiotic-resistant UPEC are increasingly common. The microenvironment of the urinary tract is metabolically distinct, and there is growing interest in understanding the extent to which metabolism may influence UPEC infection and response to antibiotics, and how this varies between individuals. Diabetes, characterized in part by glycosuria, is a known risk factor for UTI and is associated with more severe infections. The role that glucose plays in driving UPEC evolution remains unclear. Through experimental evolution with a single UPEC isolate, we identified mutations in the RNA polymerase sigma factor <i>rpoS</i> associated with long-term glucose exposure. We found that the presence of the antibiotic gentamicin resulted in mutations in genes including <i>trkH</i>, which encodes a potassium ion uptake system previously linked to aminoglycoside resistance, and in the autotransporter <i>hyxB</i>. Strikingly, these mutations were not present in populations exposed to a combination of both glucose and gentamicin. This suggests that glucose may influence the survival of mutants in gentamicin, providing new avenues for understanding the evolution and treatment of UPEC-mediated UTI in high-risk individuals.</p>","PeriodicalId":49819,"journal":{"name":"Microbiology-Sgm","volume":"171 3","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143736241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phylogenetic groups and extraintestinal virulence genes of inflow <i>Escherichia coli</i> entering a municipal drinking water treatment facility (St. Paul, MN, USA).","authors":"James R Johnson, Brian D Johnston, Paul Thuras","doi":"10.1099/mic.0.001542","DOIUrl":"10.1099/mic.0.001542","url":null,"abstract":"<p><p>Extraintestinal pathogenic <i>Escherichia coli</i> (ExPEC), a leading cause of urinary tract infections, sepsis and neonatal meningitis, circulates between diverse hosts and the environment. Consequently, identifying ExPEC reservoirs and transmission pathways has potentially great public health importance. Here, we used PCR-based methods to characterize 104 <i>E. coli</i> isolates from inflow water to the St. Paul, MN (USA), municipal drinking water treatment plant. Isolates were analysed for major phylogenetic groups and multiple extraintestinal virulence genes. Additionally, from the 65 (of 104) water samples that yielded multiple <i>E. coli</i> colonies, we screened <i>E. coli</i> population DNA for virulence genes. Thirty-three percent of isolates represented virulence-associated groups B2 and D, and 8% (95% CI: 3%, 15%) qualified molecularly as ExPEC. The ExPEC isolates, all from group B2 or D, had a median virulence gene score of 11.0 and collectively contained all but four of the 28 studied extraintestinal virulence genes. Population DNA screening increased the proportion of samples positive for individual virulence genes and, presumptively, for ExPEC [14% (95% CI: 10%, 30%) vs. 8%, <i>P</i>=0.03]. These findings identify a previously underappreciated potential mechanism for community-wide dissemination of ExPEC and underscore the importance of consistent disinfection of municipal drinking water.</p>","PeriodicalId":49819,"journal":{"name":"Microbiology-Sgm","volume":"171 3","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143732737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phosphorelay changes and plasticity underlie the life history evolution of <i>Bacillus subtilis</i> sporulation and germination in serial batch culture.","authors":"Kathleen A Sagarin, Elizabeth Ouanemalay, Hilda Asante-Nyame, Vera Hong, Chloe De Palo, Frederick M Cohan","doi":"10.1099/mic.0.001540","DOIUrl":"10.1099/mic.0.001540","url":null,"abstract":"<p><p>Bacterial endospores facilitate survival in extreme and unpredictably fluctuating environments. However, under abundant nutrient conditions, the production of endospores is quickly reduced or lost. We hypothesized that endospore-forming bacteria exposed to frequent cycling of nutrient availability would evolve reduced sporulation efficiency. We employed replicated batch culture for 11 transfers to test the effects of rapid nutrient cycles on the evolution of the life history traits of sporulation, germination and growth in <i>Bacillus subtilis</i>. We periodically measured total cell and endospore densities during the period between transfers. Replicates evolved in parallel behaviourally and genetically. By the fourth transfer, we saw a reduction in endospore production, which continued to decline throughout the experiment. Our results support a decreased likelihood of sporulation being driven by frequent nutrient renewal. The proportion of endospores germinating after transfer increased significantly by the end of the experiment through the effects of plasticity alone. Every evolved replicate culture displayed colony dimorphism: the dominant morphology being translucent with reduced sporulation ability and the rarer being opaque with accelerated sporulation and highly efficient germination. Colony dimorphism was reflected in the genomes, with all isolates with reduced sporulation having mutations in elements of the sporulation phosphorelay, particularly <i>kinA</i>. Some opaque colonies had no mutations, indicating that those adaptive changes occurred through plasticity. These results suggest that our selection conditions of nutrient cycling resulted in the parallel evolution of communities of ecologically diverse strains, where most reduced sporulation while a smaller proportion accelerated it.</p>","PeriodicalId":49819,"journal":{"name":"Microbiology-Sgm","volume":"171 3","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11914059/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143651677","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}