On the Physical Chemistry of Lipid Number-Difference Between the Leaflets of a Bilayer and Its Relevance for Quantitative Study of Bilayer Lipid Asymmetry and Associated Protein-Machinery
On the Physical Chemistry of Lipid Number-Difference Between the Leaflets of a Bilayer and Its Relevance for Quantitative Study of Bilayer Lipid Asymmetry and Associated Protein-Machinery
상세정보
- 자료유형
- 학위논문 서양
- 최종처리일시
- 20250211152656
- ISBN
- 9798384023081
- DDC
- 541
- 저자명
- Reagle, Tyler.
- 서명/저자
- On the Physical Chemistry of Lipid Number-Difference Between the Leaflets of a Bilayer and Its Relevance for Quantitative Study of Bilayer Lipid Asymmetry and Associated Protein-Machinery
- 발행사항
- [Sl] : University of Pennsylvania, 2024
- 발행사항
- Ann Arbor : ProQuest Dissertations & Theses, 2024
- 형태사항
- 183 p
- 주기사항
- Source: Dissertations Abstracts International, Volume: 86-02, Section: B.
- 주기사항
- Advisor: Baumgart, Tobias.
- 학위논문주기
- Thesis (Ph.D.)--University of Pennsylvania, 2024.
- 초록/해제
- 요약Biomembranes are extensively inhomogeneous with respect to the compositions and distribution of the lipid molecules constructing them. The lipidome of a cell and its sub-cellular distribution constitute a nonequilibrium condition maintained by i) active expenditure of cellular energy and ii) coordination of metabolic/transport processes. Though there is lipidomic/bioinformatic evidence suggesting that the above interplay is relevant for the integration of membrane biology and lipid metabolism, the thermodynamic premises underlying a hypothesized, regulatory framework have not been rigorously tested. Moreover, the role of bilayer lipid asymmetry- referring to lipid inhomogeneity between the leaflets of a lipid bilayer- has been ignored in this context. Since bilayer lipid asymmetry is a ubiquitous feature of biomembranes across cellular life, it is likely important for membrane homeostasis, necessitating further investigation.To investigate how bilayer lipid asymmetry might serve the above role, this thesis describes observations in vesicles along with a thermodynamic analysis. These were achieved by leveraging complexation between methyl-β-cyclodextrin (mbCD) and phospholipid molecules, which adjusts the difference in the number of lipid molecules (lipid number-difference) between the leaflets of vesicles. This parameter constitutes one contribution to bilayer lipid asymmetry and mbCD-lipid complexation allowed its effects upon i) vesicle morphology, ii) bilayer phase behavior, and iii) lipid thermodynamics to be investigated. Evidence suggests that lipid number-difference modulates the chemical potential (and activity) of lipids within a bilayer.Then, to investigate generation of lipid number-difference by a transmembrane protein, an active phospholipid transporter (a flippase) of the ATP-binding cassette transporter superfamily was purified and reconstituted into a bilayer environment. This was done to eventually investigate the i) conformation and ii) catalytic efficiency of flippases in this superfamily with respect to lipid number-difference (by leveraging mbCD-lipid chemistry). Challenges encountered during purification/reconstitution are described and recommended actions proposed. Achievement of the aims associated with these efforts could contextualize i) the allosteric regulation and ii) energy transduction of such proteins within a control scheme for maintenance of membrane homeostasis.
- 일반주제명
- Physical chemistry
- 일반주제명
- Biochemistry
- 일반주제명
- Biophysics
- 키워드
- Lipid membranes
- 기타저자
- University of Pennsylvania Chemistry
- 기본자료저록
- Dissertations Abstracts International. 86-02B.
- 전자적 위치 및 접속
- 로그인 후 원문을 볼 수 있습니다.
MARC
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■020 ▼a9798384023081
■035 ▼a(MiAaPQ)AAI31487492
■040 ▼aMiAaPQ▼cMiAaPQ
■0820 ▼a541
■1001 ▼aReagle, Tyler.
■24510▼aOn the Physical Chemistry of Lipid Number-Difference Between the Leaflets of a Bilayer and Its Relevance for Quantitative Study of Bilayer Lipid Asymmetry and Associated Protein-Machinery
■260 ▼a[Sl]▼bUniversity of Pennsylvania▼c2024
■260 1▼aAnn Arbor▼bProQuest Dissertations & Theses▼c2024
■300 ▼a183 p
■500 ▼aSource: Dissertations Abstracts International, Volume: 86-02, Section: B.
■500 ▼aAdvisor: Baumgart, Tobias.
■5021 ▼aThesis (Ph.D.)--University of Pennsylvania, 2024.
■520 ▼aBiomembranes are extensively inhomogeneous with respect to the compositions and distribution of the lipid molecules constructing them. The lipidome of a cell and its sub-cellular distribution constitute a nonequilibrium condition maintained by i) active expenditure of cellular energy and ii) coordination of metabolic/transport processes. Though there is lipidomic/bioinformatic evidence suggesting that the above interplay is relevant for the integration of membrane biology and lipid metabolism, the thermodynamic premises underlying a hypothesized, regulatory framework have not been rigorously tested. Moreover, the role of bilayer lipid asymmetry- referring to lipid inhomogeneity between the leaflets of a lipid bilayer- has been ignored in this context. Since bilayer lipid asymmetry is a ubiquitous feature of biomembranes across cellular life, it is likely important for membrane homeostasis, necessitating further investigation.To investigate how bilayer lipid asymmetry might serve the above role, this thesis describes observations in vesicles along with a thermodynamic analysis. These were achieved by leveraging complexation between methyl-β-cyclodextrin (mbCD) and phospholipid molecules, which adjusts the difference in the number of lipid molecules (lipid number-difference) between the leaflets of vesicles. This parameter constitutes one contribution to bilayer lipid asymmetry and mbCD-lipid complexation allowed its effects upon i) vesicle morphology, ii) bilayer phase behavior, and iii) lipid thermodynamics to be investigated. Evidence suggests that lipid number-difference modulates the chemical potential (and activity) of lipids within a bilayer.Then, to investigate generation of lipid number-difference by a transmembrane protein, an active phospholipid transporter (a flippase) of the ATP-binding cassette transporter superfamily was purified and reconstituted into a bilayer environment. This was done to eventually investigate the i) conformation and ii) catalytic efficiency of flippases in this superfamily with respect to lipid number-difference (by leveraging mbCD-lipid chemistry). Challenges encountered during purification/reconstitution are described and recommended actions proposed. Achievement of the aims associated with these efforts could contextualize i) the allosteric regulation and ii) energy transduction of such proteins within a control scheme for maintenance of membrane homeostasis.
■590 ▼aSchool code: 0175.
■650 4▼aPhysical chemistry
■650 4▼aBiochemistry
■650 4▼aBiophysics
■653 ▼aChemical equilibrium
■653 ▼aLipid membranes
■653 ▼aMembrane asymmetry
■653 ▼aMembrane morphology
■653 ▼aMethyl-beta-cyclodextrin
■690 ▼a0494
■690 ▼a0487
■690 ▼a0786
■71020▼aUniversity of Pennsylvania▼bChemistry.
■7730 ▼tDissertations Abstracts International▼g86-02B.
■790 ▼a0175
■791 ▼aPh.D.
■792 ▼a2024
■793 ▼aEnglish
■85640▼uhttp://www.riss.kr/pdu/ddodLink.do?id=T17163345▼nKERIS▼z이 자료의 원문은 한국교육학술정보원에서 제공합니다.
