著者

Tsai Melody Ohniwa Ryosuke L Kato Yusuke Takeshita Sayaka L Ohta Toshiko Saito Shinji Hayashi Hideo Morikawa Kazuya

出版者

BioMed Central

雑誌

BMC microbiology (ISSN:14712180)

巻号頁・発行日

vol.11, pp.13, 2011-01

被引用文献数

100 26

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BackgroundThe ability of staphylococci to grow in a wide range of salt concentrations is well documented. In this study, we aimed to clarify the role of cardiolipin (CL) in the adaptation of Staphylococcus aureus to high salinity.ResultsUsing an improved extraction method, the analysis of phospholipid composition suggested that CL levels increased slightly toward stationary phase, but that this was not induced by high salinity. Deletion of the two CL synthase genes, SA1155 (cls1) and SA1891 (cls2), abolished CL synthesis. The cls2 gene encoded the dominant CL synthase. In a cls2 deletion mutant, Cls1 functioned under stress conditions, including high salinity. Using these mutants, CL was shown to be unnecessary for growth in either basal or high-salt conditions, but it was critical for prolonged survival in high-salt conditions and for generation of the L-form.ConclusionsCL is not essential for S. aureus growth under conditions of high salinity, but is necessary for survival under prolonged high-salt stress and for the generation of L-form variants.

著者

Uemura Tomohiro Ueda Takashi Ohniwa Ryosuke L. Nakano Akihiko Takeyasu Kunio Sato Masa H.

出版者

日本細胞生物学会

雑誌

Cell Structure and Function

巻号頁・発行日

vol.29, no.2, pp.49-65, 2004

被引用文献数

448

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In all eucaryotic cells, specific vesicle fusion during vesicular transport is mediated by membrane-associated proteins called SNAREs (soluble N-ethyl-maleimide sensitive factor attachment protein receptors).<br> Sequence analysis identified a total of 54 SNARE genes (18 Qa-SNAREs/Syntaxins, 11 Qb-SNAREs, 8 Qc-SNAREs, 14 R-SNAREs/VAMPs and 3 SNAP-25) in the <i>Arabidopsis</i> genome. Almost all of them were ubiquitously expressed through out all tissues examined. A series of transient expression assays using green fluorescent protein (GFP) fused proteins revealed that most of the SNARE proteins were located on specific intracellular compartments: 6 in the endoplasmic reticulum, 9 in the Golgi apparatus, 4 in the <i>trans</i>-Golgi network (TGN), 2 in endosomes, 17 on the plasma membrane, 7 in both the prevacuolar compartment (PVC) and vacuoles, 2 in TGN/PVC/vacuoles, and 1 in TGN/PVC/plasma membrane.<br> Some SNARE proteins showed multiple localization patterns in two or more different organelles, suggesting that these SNAREs shuttle between the organelles. Furthermore, the SYP41/SYP61-residing compartment, which was defined as the TGN, was not always located along with the Golgi apparatus, suggesting that this compartment is an independent organelle distinct from the Golgi apparatus. We propose possible combinations of SNARE proteins on all subcellular compartments, and suggest the complexity of the post-Golgi membrane traffic in higher plant cells.<br>