Table 3.
Mass spectrometry-based detection of predicted pathogenesis-related proteins from in vivo-grown T. pallidum.
| Locus tag | Functional Annotation (Nichols strain NC_021490, July 2021 annotation) | Potential functions from previous studies* ** *** | MS detection |
|---|---|---|---|
| TPANIC_0020*** | VWA domain-containing protein | TgMIC2 (Toxoplasma gondii micronemal protein 2 A/I domain) | Present, Osbak25 |
| TPANIC_0027* | Hemolysin family protein | Putative hemolysin (HlyC) | Osbak25 |
| TPANIC_0028* | Hemolysin family protein | Putative hemolysin (HlyC) | ND |
| TPANIC_0126*** | Hypothetical protein | Outer membrane protein W (E. coli) | Present, Osbak25 |
| TPANIC_0134*** | Hypothetical protein | Bacterial sialidases/neuraminidases | Present |
| TPANIC_0225*** | Leucine-rich repeat domain-containing protein | Leucine-rich repeat surface proteins | Present |
| TPANIC_0246*** | VWA domain-containing protein | TRAP protein (Plasmodium vivax) | Osbak25 |
| TPANIC_0262** | Crp/Fnr family transcriptional regulator | PrfA (Listeria monocytogenes virulence factor transcriptional regulator) | Present, Osbak25 |
| TPANIC_0399* | Flagellar M-ring protein FliF | Type 3 (virulence-related) secretory pathway protein (FliF) | Present, Osbak25 |
| TPANIC_0401* | Flagellar assembly protein FliH | Type 3 (virulence-related) secretory pathway protein (FliH) | Present, Osbak25 |
| TPANIC_0402* | Flagellar protein export ATPase FliI | Type 3 (virulence-related) secretory pathway protein (FliL) | Present, Osbak25 |
| TPANIC_0421*** | Tetratricopeptide repeat protein | PknD (Mycobacterium tuberculosis serine/threonine protein kinase, extracellular domain) | Present, Osbak25 |
| TPANIC_0544*** | SpnA family nuclease | SmcL (Listeria ivanovii Sphingomyelinase-C) | Present, Osbak25 |
| TPANIC_0579*** | Hypothetical protein |
YenC2 (Yersinia entomophaga ABC toxin; BC component) |
Osbak25 |
| TPANIC_0594*** | DUF2147 domain-containing protein | HP1028 (Helicobacter pylori lipocalin) | Present |
| TPANIC_0598*** | Hypothetical protein | BamB (Moraxella catarrhalis Beta barrel assembly machinery protein B) | Present, Osbak25 |
| TPANIC_0625*** | Hypothetical protein |
BamD (Beta barrel assembly machinery protein) (Rhodothermus marinus, E. coli) |
Present, Osbak25 |
| TPANIC_0649* | Hemolysin family protein | Putative hemolysin (TlyC) | Present, Osbak25 |
| TPANIC_0714* | Flagellar biosynthesis protein FlhA | Type 3 (virulence-related) secretory pathway protein (FlhA) | Present, Osbak25 |
| TPANIC_0715* | Flagellar biosynthesis protein FlhB | Type 3 (virulence-related) secretory pathway protein (FlhB) | Present, Osbak25 |
| TPANIC_0733*** | Outer membrane beta-barrel protein | NspA (Neisseria surface protein A) | Present |
| TPANIC_0783*** | Hypothetical protein | BamB (E. coli beta barrel assembly machinery protein B) | Present |
| TPANIC_0789*** | Outer membrane lipoprotein-sorting protein |
LolA (P. aeruginosa outer- membrane lipoprotein carrier/localization protein) |
Present, Osbak25, McGill24 |
| TPANIC_0854*** | SpoIIE family protein phosphatase | Bacterial sialidases/neuraminidases | Present, Osbak25 |
| TPANIC_0862** | FKBP-type peptidyl-prolyl cis–trans isomerase | Mip (Legionella pneumophila macrophage infectivity potentiator protein) | Present, McGill24 |
| TPANIC_0911*** | FlhB-like flagellar biosynthesis protein | EscU (E. coli type 3 secretion system protein) | ND |
| TPANIC_0928*** | Hypothetical protein (previous proteome annotation; not annotated in July 2021) | SurA (E. coli chaperone) | Present, Osbak25 |
| TPANIC_0936* | Hemolysin family protein | Putative hemolysin | ND |
| TPANIC_0966*** | Hypothetical protein | TolC (E. coli outer membrane channel protein) | Present |
| TPANIC_0967*** | Hypothetical protein | TolC (E. coli outer membrane channel protein) | Present, Osbak25 |
| TPANIC_0968*** | Hypothetical protein | TolC (E. coli outer membrane channel protein) | Present, Osbak25 |
| TPANIC_0969*** | Hypothetical protein | TolC (E. coli outer membrane channel protein) | Present, Osbak25, McGill24 |
| TPANIC_1033** | Patatin-like phospholipase family protein | VipD (Legionella pneumophila phospholipase effector protein) | Present, Osbak25 |
| TPANIC_1037* | Hemolysin III family protein | Putative hemolysin III (HlyIII) | Present |
*Proteins identified as potential virulence factors in T. pallidum genome sequencing and comparison studies35, 54, 55.
**Proteins identified as novel virulence factor candidates (proteins previously annotated with non-virulence related functions) using whole proteome structure modeling (highest-ranking predicted virulence-related structural homolog listed)50.
***Proteins identified as novel virulence factor candidates (proteins of unknown function) using whole proteome structure modeling (highest-ranking predicted virulence-related structural homolog listed)50.
ND: Protein not detected.
McGill: Proteins detected in McGill et al. study (2010). Osbak: Proteins detected in Osbak et al. study (2016). Present: Proteins detected in the present study (Present: protein identification based on the detection of one tryptic peptide).
Proteins in bold font: Proteins from in vivo-grown T. pallidum that were identified only in the present study.