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Sura Ali Benjamin Jenkins Jiujun Cheng Briallen Lobb Xin Wei Suhelen Egan Trevor C. Charles Brendan J. McConkey John Austin Andrew C. Doxey 《Molecular microbiology》2020,114(6):979-990
S-layers are paracrystalline proteinaceous lattices that surround prokaryotic cells, forming a critical interface between the cells and their extracellular environment. Here, we report the discovery of a novel S-layer protein present in the Gram-negative marine organism, Pseudoalteromonas tunicata D2. An uncharacterized protein (EAR28894) was identified as the most abundant protein in planktonic cultures and biofilms. Bioinformatic methods predicted a beta-helical structure for EAR28894 similar to the Caulobacter S-layer protein, RsaA, despite sharing less than 20% sequence identity. Transmission electron microscopy revealed that purified EAR28894 protein assembled into paracrystalline sheets with a unique square lattice symmetry and a unit cell spacing of ~9.1 nm. An S-layer was found surrounding the outer membrane in wild-type cells and completely removed from cells in an EAR28894 deletion mutant. S-layer material also appeared to be “shed” from wild-type cells and was highly abundant in the extracellular matrix where it is associated with outer membrane vesicles and other matrix components. EAR28894 and its homologs form a new family of S-layer proteins that are widely distributed in Gammaproteobacteria including species of Pseudoalteromonas and Vibrio, and found exclusively in marine metagenomes. We propose the name Slr4 for this novel protein family. 相似文献
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Chen Youchao Ma Shuqin Jiang Hongmao Yangzom Degyi Cheng Genwei Lu Xuyang 《Plant and Soil》2021,459(1-2):23-35
Plant and Soil - In the context of rapid species diversity loss, whether and how species diversity affects litter decomposition in alpine ecosystems remain unclear. Here, we aimed to assess the... 相似文献
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Zhang Wenwen Xue Fang Xie Shangdan Chen Cheng Li Jingwei Zhu Xueqiong 《Molecular and cellular biochemistry》2021,476(1):45-55
Molecular and Cellular Biochemistry - This study investigated the effect of isoflurane on the proliferation of squamous cervical cancer cells, with focus on histone deacetylase 6 that is closely... 相似文献
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Chai Qian Meng Ziang Lu Dexue Zhang Ziying Liu Meili Wu Weihua 《Molecular and cellular biochemistry》2021,476(6):2479-2489
Molecular and Cellular Biochemistry - Cardiomyocyte death is an important pathogenic process in cardiac complications of diabetes. Diabetic patients often suffer glycemic variability. Pyroptosis is... 相似文献