Suthi Subbarayudu, P Snega priya, Rajakrishnan Rajagopal, Ahmed Alfarhan, Ajay Guru, Jesu Arockiaraj
{"title":"酸性和碱性条件对金黄色葡萄球菌和鲍曼不动杆菌相互作用及其生物膜的影响。","authors":"Suthi Subbarayudu, P Snega priya, Rajakrishnan Rajagopal, Ahmed Alfarhan, Ajay Guru, Jesu Arockiaraj","doi":"10.1007/s00203-024-04142-w","DOIUrl":null,"url":null,"abstract":"<div><p>Bacterial biofilms pose significant challenges due to their association with antibiotic resistance, metabolic adaptation, and survival under harsh conditions. Among notable pathogens forming biofilms, <i>Staphylococcus aureus</i> and <i>Acinetobacter baumannii</i> are concerning pathogens in nosocomial settings. However, their behaviour under acidic (pH 4.5) and alkaline (pH10.5) conditions, especially in co-culture setups, remains insufficiently understood. This study investigates these aspects, by examining growth rates, biofilm formation, pH shifts, phenotypic analysis, and gene expression profiles. The results showed <i>A. baumannii</i> exhibited reduced growth and biofilm formation at pH 4.5, while <i>S. aureus</i> showed slow growth and low biofilm formation at pH10.5 in mono-cultures<i>. S. aureus</i> leaned towards an acidic pH (6–6.5), whereas <i>A. baumannii</i> shifted towards an alkaline pH (8–9). In co-culture environments, growth rates and biofilm formation increased across all pH conditions, converging towards a neutral pH over time. Phenotypic motility assays indicated that <i>A. baumannii</i> exhibited greater motility in alkaline conditions, while <i>S. aureus</i> showed increased staphyloxanthin production under acidic conditions. Gene expression analyses revealed that the fibronectin-binding protein A (<i>FnbA</i>) and N-acetylglucosaminyl-transferase (<i>icaA</i>) genes, responsible for initial attachment during biofilm formation, were highly expressed in acidic co-culture condition but poorly expressed in alkaline condition. In <i>A. baumannii</i>, the outer membrane protein A (<i>OmpA</i>) gene associated with adhesion and virulence, was upregulated in co-culture. The <i>LuxR</i> gene involved in quorum sensing was upregulated in acidic conditions and poorly expressed at pH 10.5. This study elucidates the metabolic adaptability and biofilm formation tendencies of <i>S. aureus</i> towards acidic conditions and <i>A. baumannii</i> towards alkaline conditions, providing insights for better management of biofilm-related infections.</p></div>","PeriodicalId":8279,"journal":{"name":"Archives of Microbiology","volume":"206 11","pages":""},"PeriodicalIF":2.3000,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Impact of acidic and alkaline conditions on Staphylococcus aureus and Acinetobacter baumannii interactions and their biofilms\",\"authors\":\"Suthi Subbarayudu, P Snega priya, Rajakrishnan Rajagopal, Ahmed Alfarhan, Ajay Guru, Jesu Arockiaraj\",\"doi\":\"10.1007/s00203-024-04142-w\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Bacterial biofilms pose significant challenges due to their association with antibiotic resistance, metabolic adaptation, and survival under harsh conditions. Among notable pathogens forming biofilms, <i>Staphylococcus aureus</i> and <i>Acinetobacter baumannii</i> are concerning pathogens in nosocomial settings. However, their behaviour under acidic (pH 4.5) and alkaline (pH10.5) conditions, especially in co-culture setups, remains insufficiently understood. This study investigates these aspects, by examining growth rates, biofilm formation, pH shifts, phenotypic analysis, and gene expression profiles. The results showed <i>A. baumannii</i> exhibited reduced growth and biofilm formation at pH 4.5, while <i>S. aureus</i> showed slow growth and low biofilm formation at pH10.5 in mono-cultures<i>. S. aureus</i> leaned towards an acidic pH (6–6.5), whereas <i>A. baumannii</i> shifted towards an alkaline pH (8–9). In co-culture environments, growth rates and biofilm formation increased across all pH conditions, converging towards a neutral pH over time. Phenotypic motility assays indicated that <i>A. baumannii</i> exhibited greater motility in alkaline conditions, while <i>S. aureus</i> showed increased staphyloxanthin production under acidic conditions. Gene expression analyses revealed that the fibronectin-binding protein A (<i>FnbA</i>) and N-acetylglucosaminyl-transferase (<i>icaA</i>) genes, responsible for initial attachment during biofilm formation, were highly expressed in acidic co-culture condition but poorly expressed in alkaline condition. In <i>A. baumannii</i>, the outer membrane protein A (<i>OmpA</i>) gene associated with adhesion and virulence, was upregulated in co-culture. The <i>LuxR</i> gene involved in quorum sensing was upregulated in acidic conditions and poorly expressed at pH 10.5. This study elucidates the metabolic adaptability and biofilm formation tendencies of <i>S. aureus</i> towards acidic conditions and <i>A. baumannii</i> towards alkaline conditions, providing insights for better management of biofilm-related infections.</p></div>\",\"PeriodicalId\":8279,\"journal\":{\"name\":\"Archives of Microbiology\",\"volume\":\"206 11\",\"pages\":\"\"},\"PeriodicalIF\":2.3000,\"publicationDate\":\"2024-10-08\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Archives of Microbiology\",\"FirstCategoryId\":\"99\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s00203-024-04142-w\",\"RegionNum\":3,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"MICROBIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Archives of Microbiology","FirstCategoryId":"99","ListUrlMain":"https://link.springer.com/article/10.1007/s00203-024-04142-w","RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MICROBIOLOGY","Score":null,"Total":0}
Impact of acidic and alkaline conditions on Staphylococcus aureus and Acinetobacter baumannii interactions and their biofilms
Bacterial biofilms pose significant challenges due to their association with antibiotic resistance, metabolic adaptation, and survival under harsh conditions. Among notable pathogens forming biofilms, Staphylococcus aureus and Acinetobacter baumannii are concerning pathogens in nosocomial settings. However, their behaviour under acidic (pH 4.5) and alkaline (pH10.5) conditions, especially in co-culture setups, remains insufficiently understood. This study investigates these aspects, by examining growth rates, biofilm formation, pH shifts, phenotypic analysis, and gene expression profiles. The results showed A. baumannii exhibited reduced growth and biofilm formation at pH 4.5, while S. aureus showed slow growth and low biofilm formation at pH10.5 in mono-cultures. S. aureus leaned towards an acidic pH (6–6.5), whereas A. baumannii shifted towards an alkaline pH (8–9). In co-culture environments, growth rates and biofilm formation increased across all pH conditions, converging towards a neutral pH over time. Phenotypic motility assays indicated that A. baumannii exhibited greater motility in alkaline conditions, while S. aureus showed increased staphyloxanthin production under acidic conditions. Gene expression analyses revealed that the fibronectin-binding protein A (FnbA) and N-acetylglucosaminyl-transferase (icaA) genes, responsible for initial attachment during biofilm formation, were highly expressed in acidic co-culture condition but poorly expressed in alkaline condition. In A. baumannii, the outer membrane protein A (OmpA) gene associated with adhesion and virulence, was upregulated in co-culture. The LuxR gene involved in quorum sensing was upregulated in acidic conditions and poorly expressed at pH 10.5. This study elucidates the metabolic adaptability and biofilm formation tendencies of S. aureus towards acidic conditions and A. baumannii towards alkaline conditions, providing insights for better management of biofilm-related infections.
期刊介绍:
Research papers must make a significant and original contribution to
microbiology and be of interest to a broad readership. The results of any
experimental approach that meets these objectives are welcome, particularly
biochemical, molecular genetic, physiological, and/or physical investigations into
microbial cells and their interactions with their environments, including their eukaryotic hosts.
Mini-reviews in areas of special topical interest and papers on medical microbiology, ecology and systematics, including description of novel taxa, are also published.
Theoretical papers and those that report on the analysis or ''mining'' of data are
acceptable in principle if new information, interpretations, or hypotheses
emerge.