Streptococcus gordonii Type I Lipoteichoic Acid Contributes to Surface Protein Biogenesis.
Streptococcus gordonii Type I Lipoteichoic Acid Contributes to Surface Protein Biogenesis.
复制标题
戈登链球菌 I 型脂磷壁酸有助于表面蛋白的生物合成。
DOI：
10.1128/msphere.00814-19
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发表时间：
2019
期刊：
影响因子：
4.8
通讯作者：
Herzberg,MarkC
中科院分区：
文献类型：
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作者：
Lima,BrunoP;Kho,Kelvin;Nairn,BrittanyL;Davies,JuliaR;Svensäter,Gunnel;Chen,Ruoqiong;Steffes,Amanda;Vreeman,GerritW;Meredith,TimothyC;Herzberg,MarkC
脂磷壁酸（LTA）是革兰氏阳性菌细胞膜中丰富的聚合物，对许多物种都是必需的。尽管LTA的确切功能尚未阐明，但在某些物种中LTA的丧失会影响疏水性、生物膜形成和细胞分裂。使用一个可行的LTA缺陷株的人口腔唾液链球菌戈登，我们证明了LTA在表面蛋白的介绍中起着重要的作用。细胞壁组分来源于野生型和LTA缺陷型菌株的S。使用无标记质谱分析Gordonii。比较结果表明，许多蛋白质的丰度不同，包括（i）SspA，SspB，和S。gordonii 0707（SGO_0707）（生物膜形成）;（ii）FtsE（细胞分裂）;（iii）Pbp 1a和Pbp 2a（细胞壁生物合成和重塑）;和（iv）DegP（包膜应激反应）。细胞表面蛋白质呈递的这些变化似乎解释了我们观察到的改变的细胞包膜稳态、生物膜形成和与真核细胞的粘附，而不影响与其他细菌物种的结合和共聚集，并提供了对其他革兰氏阳性细菌物种中LTA丢失所揭示的表型的深入了解。我们还对S. gordonii。与猪链球菌相似，S. gordonii产生了一个复杂的I型LTA，装饰有多重alanylation和糖基化。因此，S.戈登氏菌LTA似乎协调细胞表面相关蛋白和功能的表达和呈递。重要性脂磷壁酸（LTA）是在半个多世纪前发现的，是在革兰氏阳性菌表面发现的丰富的聚合物。虽然LTA对于许多革兰氏阳性菌的生存至关重要，但关于LTA如何促进细菌生理学的知识仍然难以捉摸。最近，在一些革兰氏阳性菌种中产生了LTA缺陷型菌株，包括人口腔链球菌戈登氏链球菌。本研究的意义在于利用了一株LTA缺陷型沙门氏菌。gordonii来解决为什么LTA对革兰氏阳性菌具有生理重要性。我们证明，在S。gordonii，LTA在许多细胞表面相关蛋白的呈递中起重要作用，有助于细胞包膜稳态、生物膜中的细胞与细胞相互作用以及对真核细胞的粘附。这些数据可以广泛地反映LTA在革兰氏阳性菌中的生理作用。
Lipoteichoic acid (LTA) is an abundant polymer of the Gram-positive bacterial cell envelope and is essential for many species. Whereas the exact function of LTA has not been elucidated, loss of LTA in some species affects hydrophobicity, biofilm formation, and cell division. Using a viable LTA-deficient strain of the human oral commensal Streptococcus gordonii, we demonstrated that LTA plays an important role in surface protein presentation. Cell wall fractions derived from the wild-type and LTA-deficient strains of S. gordonii were analyzed using label-free mass spectroscopy. Comparisons showed that the abundances of many proteins differed, including (i) SspA, SspB, and S. gordonii 0707 (SGO_0707) (biofilm formation); (ii) FtsE (cell division); (iii) Pbp1a and Pbp2a (cell wall biosynthesis and remodeling); and (iv) DegP (envelope stress response). These changes in cell surface protein presentation appear to explain our observations of altered cell envelope homeostasis, biofilm formation, and adhesion to eukaryotic cells, without affecting binding and coaggregation with other bacterial species, and provide insight into the phenotypes revealed by the loss of LTA in other species of Gram-positive bacteria. We also characterized the chemical structure of the LTA expressed by S. gordonii. Similarly to Streptococcus suis, S. gordonii produced a complex type I LTA, decorated with multipled-alanylations and glycosylations. Hence, the S. gordonii LTA appears to orchestrate expression and presentation of cell surface-associated proteins and functions.IMPORTANCEDiscovered over a half-century ago, lipoteichoic acid (LTA) is an abundant polymer found on the surface of Gram-positive bacteria. Although LTA is essential for the survival of many Gram-positive species, knowledge of how LTA contributes to bacterial physiology has remained elusive. Recently, LTA-deficient strains have been generated in some Gram-positive species, including the human oral commensal Streptococcus gordonii. The significance of our research is that we utilized an LTA-deficient strain of S. gordonii to address why LTA is physiologically important to Gram-positive bacteria. We demonstrate that in S. gordonii, LTA plays an important role in the presentation of many cell surface-associated proteins, contributing to cell envelope homeostasis, cell-to-cell interactions in biofilms, and adhesion to eukaryotic cells. These data may broadly reflect a physiological role of LTA in Gram-positive bacteria.