Table 1.
Summary table.
| Dimerization | Phosphorylation | PDase activity | Gingipains secretion | ||||
|---|---|---|---|---|---|---|---|
| PorXFJ | AcP | Zn | REC | APS | PorXPG | ||
| WT | + | + | + | + | + | WT | +++ |
| D54A | − | + | − | + | + | D58A | ++ |
| T271V | + | + | + | − | − | T272V | ++ |
| L113E | − | + | + | + | + | L117E | + |
| D54A & T271V | − | + | − | − | − | D58A & T272V | + |
| D360A & H364A | + | − | + | − | − | D361A & H365A | + |
| S384A & S388E | + | − | + | + | − | S385A & S389E | +++ |
| REC domain (1–121) | + | + | + | n/a | − | REC domain (1–125) | + |
| REC + THB domains (1–208) | (+) | (+) | + | n/a | − | REC + THB domains (1–207) | + |
| APS + THB domains (126–end) | − | + | n/a | + | + | APS + THB domains (130–end) | + |
Results of the in vitro and in vivo characterization of PorX and its variants presented throughout the manuscript. In vitro characterization results include oligomeric state analyses by size exclusion chromatography, phosphorylation assays by intact protein MS analysis, and phosphodiesterase (PDase) assays. In vivo characterization results include the gingipain activity assays representing the T9SS's ability to secret gingipains in P. gingivalis. The symbols “+”, “++,” and “+++” in the gingipain secretion column represent average gingipain activities ranging from 0 to 33, 34 to 66, and 67 to 100%, respectively. The “n/a” indicates that phosphorylation could not be detected as the APS domain was truncated in this construct. The symbol “(+)” indicates that REC + THB domains truncated variant existed as a dimer even before the introduction of dimerizing agent.