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).