In-Depth Proteome Coverage of In Vitro-Cultured Treponema pallidum and Quantitative Comparison Analyses with In Vivo-Grown Treponemes

Previous mass spectrometry
(MS)-based global proteomics studies
have detected a combined total of 86% of all Treponema
pallidum proteins under infection conditions (in vivo-grown T. pallidum). Recently, a method was developed for
the long-term culture of T. pallidum under in vitro conditions (in vitro-cultured T. pallidum). Herein, we used our previously reported optimized MS-based proteomics
approach to characterize the T. pallidum global protein expression profile under in vitro culture conditions.
These analyses provided a proteome coverage of 94%, which extends
the combined T. pallidum proteome coverage
from the previously reported 86% to a new combined total of 95%. This
study provides a more complete understanding of the protein repertoire
of T. pallidum. Further, comparison
of the in vitro-expressed proteome with the previously determined
in vivo-expressed proteome identifies only a few proteomic changes
between the two growth conditions, reinforcing the suitability of
in vitro-cultured T. pallidum as an
alternative to rabbit-based treponemal growth. The MS proteomics data
have been deposited in the MassIVE repository with the data set identifier
MSV000093603 (ProteomeXchange identifier PXD047625).

以往基于质谱（mass spectrometry, MS）的全局蛋白质组学研究，在感染状态下（即体内培养的梅毒螺旋体（Treponema pallidum））已累计共检测到该菌种全部蛋白质的86%。近期，科研人员开发出可长期体外培养梅毒螺旋体的方法，获得体外培养的梅毒螺旋体。本研究采用此前报道的优化型基于质谱的蛋白质组学方法，对体外培养条件下梅毒螺旋体的全局蛋白质表达谱进行了系统表征。本次分析实现了94%的蛋白质组覆盖度，将此前报道的86%梅毒螺旋体蛋白质组总覆盖度提升至95%的新水平。本研究使学界对梅毒螺旋体的蛋白质组全貌有了更为完整的认知。进一步将体外培养梅毒螺旋体的表达蛋白质组与此前测定的体内感染状态表达蛋白质组进行比对，仅发现两种培养条件下存在少量蛋白质组学差异，进一步佐证了体外培养的梅毒螺旋体可替代家兔培养体系用于梅毒螺旋体相关研究。本研究产生的质谱蛋白质组学数据已提交至MassIVE数据库，数据集标识符为MSV000093603（ProteomeXchange标识符为PXD047625）。