Diderm bacteria,characterized by an additional lipid membrane layer known as the outer membrane,fold their outer membrane proteins(OMPs)via theβ-barrel assembly machinery(BAM)complex.Understanding how the BAM complex...Diderm bacteria,characterized by an additional lipid membrane layer known as the outer membrane,fold their outer membrane proteins(OMPs)via theβ-barrel assembly machinery(BAM)complex.Understanding how the BAM complex,particularly its key component BamA,assists in OMP folding remains crucial in bacterial cell biology.Recent research has focused primarily on the structural and functional characteristics of BamA within the Gracilicutes clade,such as in Escherichia coli(E.coli).However,another major evolutionary branch,Terrabacteria,has received comparatively less attention.An example of a Terrabacteria is Deinococcus radiodurans(D.radiodurans),a Gram-positive bacterium that possesses a distinctive outer membrane structure.In this study,we first demonstrated that theβ-barrel domains of BamA are not interchangeable between D.radiodurans and E.coli.The structure of D.radiodurans BamA was subsequently determined at 3.8Åresolution using cryo-electron microscopy,revealing obviously distinct arrangements of extracellular loop 4(ECL4)and ECL6 after structural comparison with their counterparts in gracilicutes.Despite the overall similarity in the topology of theβ-barrel domain,our results indicate that certain ECLs have evolved into distinct structures between the Terrabacteria and Gracilicutes clades.While BamA and its function are generally conserved across diderm bacterial species,our findings underscore the evolutionary diversity of this core OMP folder among bacteria,offering new insights into bacterial physiology and evolutionary biology.展开更多
真核生物细胞中,双层膜细胞器线粒体会进行持续的分裂与融合,从而改变自身形态来满足细胞在不同生长条件下的能量代谢需求.除此之外,线粒体的动态与功能还依赖于与其他细胞器的互作及一些代谢产物在互作过程中的双向交流.与线粒体互作...真核生物细胞中,双层膜细胞器线粒体会进行持续的分裂与融合,从而改变自身形态来满足细胞在不同生长条件下的能量代谢需求.除此之外,线粒体的动态与功能还依赖于与其他细胞器的互作及一些代谢产物在互作过程中的双向交流.与线粒体互作的细胞器包括脂滴、过氧化物酶体、液泡和内质网等.在真菌细胞中,线粒体与内质网的互作由存在二者之间的内质网-线粒体接触复合物(ER and mitochondria encounter structure,ERMES)介导.ERMES复合物对于维持线粒体的形态和功能至关重要,其破坏会影响线粒体的动态、钙离子信号、磷脂组分的转运、真菌耐药性和致病真菌的毒力等.本文着重对ERMES复合物在真菌细胞中的组装、功能及其组装调控机制进行系统的总结和讨论.展开更多
基金supported by the Fundamental Research Funds for the Central Universities(WK9100000063)the Fundamental Research Funds for the Central Universities(WK9100000031)+3 种基金the National Natural Science Foundation of China(32270035,32271241)the Anhui Provincial Natural Science Foundation(2208085MC40,2008085QC98)the Talent Fund Project of Biomedical Sciences and Health Laboratory of Anhui Province,University of Science and Technology of China(BJ9100000003)the start-up funding from the University of Science and Technology of China(KY9100000034,KJ2070000082).
文摘Diderm bacteria,characterized by an additional lipid membrane layer known as the outer membrane,fold their outer membrane proteins(OMPs)via theβ-barrel assembly machinery(BAM)complex.Understanding how the BAM complex,particularly its key component BamA,assists in OMP folding remains crucial in bacterial cell biology.Recent research has focused primarily on the structural and functional characteristics of BamA within the Gracilicutes clade,such as in Escherichia coli(E.coli).However,another major evolutionary branch,Terrabacteria,has received comparatively less attention.An example of a Terrabacteria is Deinococcus radiodurans(D.radiodurans),a Gram-positive bacterium that possesses a distinctive outer membrane structure.In this study,we first demonstrated that theβ-barrel domains of BamA are not interchangeable between D.radiodurans and E.coli.The structure of D.radiodurans BamA was subsequently determined at 3.8Åresolution using cryo-electron microscopy,revealing obviously distinct arrangements of extracellular loop 4(ECL4)and ECL6 after structural comparison with their counterparts in gracilicutes.Despite the overall similarity in the topology of theβ-barrel domain,our results indicate that certain ECLs have evolved into distinct structures between the Terrabacteria and Gracilicutes clades.While BamA and its function are generally conserved across diderm bacterial species,our findings underscore the evolutionary diversity of this core OMP folder among bacteria,offering new insights into bacterial physiology and evolutionary biology.
基金supported by the National Key R&D Program of China (2022YFA1303100, 2022YFA0806800)the National Natural Science Foundation of China (32090040, 31621002, 31871359, 32170733, 92153302)+1 种基金the Ministry of Education (IRT_17R102, 20113402130010, YD2070006001)the Fundamental Research Funds for the Central Universities (WK2070000194)
文摘真核生物细胞中,双层膜细胞器线粒体会进行持续的分裂与融合,从而改变自身形态来满足细胞在不同生长条件下的能量代谢需求.除此之外,线粒体的动态与功能还依赖于与其他细胞器的互作及一些代谢产物在互作过程中的双向交流.与线粒体互作的细胞器包括脂滴、过氧化物酶体、液泡和内质网等.在真菌细胞中,线粒体与内质网的互作由存在二者之间的内质网-线粒体接触复合物(ER and mitochondria encounter structure,ERMES)介导.ERMES复合物对于维持线粒体的形态和功能至关重要,其破坏会影响线粒体的动态、钙离子信号、磷脂组分的转运、真菌耐药性和致病真菌的毒力等.本文着重对ERMES复合物在真菌细胞中的组装、功能及其组装调控机制进行系统的总结和讨论.