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Characterization of Ca²⁺-Mediated Virulence and Microbial Competition in the Plant Pathogen Pseudomonas syringae
Characterization of Ca²⁺-Mediated Virulence and Microbial Competition in the Plant Pathogen Pseudomonas syringae
상세정보
- 자료유형
- 학위논문 서양
- 최종처리일시
- 20260202104813
- ISBN
- 9798293823796
- DDC
- 581
- 저자명
- Wan, Lingwei.
- 서명/저자
- Characterization of Ca²⁺-Mediated Virulence and Microbial Competition in the Plant Pathogen Pseudomonas syringae
- 발행사항
- [Sl] : Cornell University, 2025
- 발행사항
- Ann Arbor : ProQuest Dissertations & Theses, 2025
- 형태사항
- 213 p
- 주기사항
- Source: Dissertations Abstracts International, Volume: 87-03, Section: B.
- 주기사항
- Includes supplementary digital materials.
- 주기사항
- Advisor: Filiatrault, Melanie.
- 학위논문주기
- Thesis (Ph.D.)--Cornell University, 2025.
- 초록/해제
- 요약Calcium ions (Ca²⁺) are ubiquitous signaling molecules that play critical roles across all domains of life. In plants, Ca²⁺ acts as a central second messenger that transduces a wide array of biotic and abiotic signals, including those triggered during interactions with microbial pathogens. Upon pathogen recognition, plants often exhibit rapid and localized Ca²⁺ influxes that initiate downstream immune responses. However, the role of Ca²⁺ is not restricted to the host; many bacterial pathogens have evolved mechanisms to sense and respond to environmental Ca²⁺ levels, using these signals to fine-tune their physiology and coordinate virulence.Pseudomonas syringae, a model bacterial plant pathogen, uses a sophisticated arsenal of virulence factors, including the type III secretion system (T3SS), virulence factors, and phytotoxins, to manipulate plant cellular processes and suppress immunity. Emerging evidence suggests that Ca²⁺ serves as an important environmental cue that modulates the expression and activity of these virulence determinants. Despite this, the molecular mechanisms by which Ca²⁺ regulates bacterial pathogenicity, and the ecological consequences of such regulation, remain poorly understood.In Chapter 2, I characterized cynT, which encodes for a β-class carbonic anhydrase, by comparative transcriptomics. The transcriptomics analysis across different media and conditions supplemented with calcium revealed that cynT influences the expression of virulence and metabolic genes in a context-dependent manner, and deletion of cynT impact phenotypes of P. syringae. In Chapter 3, I investigated the srfABC operon, which was found to be regulated by cynT. Functional assays revealed that srfABC contributes to both virulence and interbacterial competition. Analysis of SrfA indicated it is secreted by P.syringae in a T3- and T6- independent manner. In Chapter 4, I explored how calcium modulates the activity of type VI secretion system (T6SS)-dependent competition. I found that calcium enhances T6SS-mediated killing against E.coli. Further analyses implicated GacAS plays a key role in integrating calcium signals to modulate T6SS activity.By dissecting the regulatory networks and physiological outcomes linked to Ca²⁺ sensing, this work provides new insights into how bacterial pathogens exploit host and environmental cues to establish infection and outcompete microbial rivals. These findings underscore the importance of calcium as an environmental signal shaping both virulence and microbial interactions in plant-associated bacteria.
- 일반주제명
- Plant pathology
- 일반주제명
- Microbiology
- 일반주제명
- Cellular biology
- 일반주제명
- Plant sciences
- 키워드
- Calcium ions
- 기타저자
- Cornell University Plant Pathology and Plant-Microbe Biology
- 기본자료저록
- Dissertations Abstracts International. 87-03B.
- 전자적 위치 및 접속
- 로그인 후 원문을 볼 수 있습니다.
MARC
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■006m o d
■007cr#unu||||||||
■020 ▼a9798293823796
■035 ▼a(MiAaPQ)AAI32167758
■040 ▼aMiAaPQ▼cMiAaPQ
■0820 ▼a581
■1001 ▼aWan, Lingwei.▼0(orcid)0000-0003-4304-1665
■24510▼aCharacterization of Ca²⁺-Mediated Virulence and Microbial Competition in the Plant Pathogen Pseudomonas syringae
■260 ▼a[Sl]▼bCornell University▼c2025
■260 1▼aAnn Arbor▼bProQuest Dissertations & Theses▼c2025
■300 ▼a213 p
■500 ▼aSource: Dissertations Abstracts International, Volume: 87-03, Section: B.
■500 ▼aIncludes supplementary digital materials.
■500 ▼aAdvisor: Filiatrault, Melanie.
■5021 ▼aThesis (Ph.D.)--Cornell University, 2025.
■520 ▼aCalcium ions (Ca²⁺) are ubiquitous signaling molecules that play critical roles across all domains of life. In plants, Ca²⁺ acts as a central second messenger that transduces a wide array of biotic and abiotic signals, including those triggered during interactions with microbial pathogens. Upon pathogen recognition, plants often exhibit rapid and localized Ca²⁺ influxes that initiate downstream immune responses. However, the role of Ca²⁺ is not restricted to the host; many bacterial pathogens have evolved mechanisms to sense and respond to environmental Ca²⁺ levels, using these signals to fine-tune their physiology and coordinate virulence.Pseudomonas syringae, a model bacterial plant pathogen, uses a sophisticated arsenal of virulence factors, including the type III secretion system (T3SS), virulence factors, and phytotoxins, to manipulate plant cellular processes and suppress immunity. Emerging evidence suggests that Ca²⁺ serves as an important environmental cue that modulates the expression and activity of these virulence determinants. Despite this, the molecular mechanisms by which Ca²⁺ regulates bacterial pathogenicity, and the ecological consequences of such regulation, remain poorly understood.In Chapter 2, I characterized cynT, which encodes for a β-class carbonic anhydrase, by comparative transcriptomics. The transcriptomics analysis across different media and conditions supplemented with calcium revealed that cynT influences the expression of virulence and metabolic genes in a context-dependent manner, and deletion of cynT impact phenotypes of P. syringae. In Chapter 3, I investigated the srfABC operon, which was found to be regulated by cynT. Functional assays revealed that srfABC contributes to both virulence and interbacterial competition. Analysis of SrfA indicated it is secreted by P.syringae in a T3- and T6- independent manner. In Chapter 4, I explored how calcium modulates the activity of type VI secretion system (T6SS)-dependent competition. I found that calcium enhances T6SS-mediated killing against E.coli. Further analyses implicated GacAS plays a key role in integrating calcium signals to modulate T6SS activity.By dissecting the regulatory networks and physiological outcomes linked to Ca²⁺ sensing, this work provides new insights into how bacterial pathogens exploit host and environmental cues to establish infection and outcompete microbial rivals. These findings underscore the importance of calcium as an environmental signal shaping both virulence and microbial interactions in plant-associated bacteria.
■590 ▼aSchool code: 0058.
■650 4▼aPlant pathology
■650 4▼aMicrobiology
■650 4▼aCellular biology
■650 4▼aPlant sciences
■653 ▼aCalcium ions
■653 ▼aType III secretion system
■653 ▼aMicrobial competition
■653 ▼aPseudomonas syringae
■690 ▼a0480
■690 ▼a0410
■690 ▼a0379
■690 ▼a0479
■71020▼aCornell University▼bPlant Pathology and Plant-Microbe Biology.
■7730 ▼tDissertations Abstracts International▼g87-03B.
■790 ▼a0058
■791 ▼aPh.D.
■792 ▼a2025
■793 ▼aEnglish
■85640▼uhttp://www.riss.kr/pdu/ddodLink.do?id=T17358948▼nKERIS▼z이 자료의 원문은 한국교육학술정보원에서 제공합니다.


