TABLE 2.

Proteins modulated in PAO1 and mep72 secretome^a

Function and PA no.	Master no.	Gene name	Gene product	Level of abundanceb	Fold modulation
Spots displaying increased abundance in the wild-type (PAO1) secretome
PA2783	1426	mep72	Metzincin protease Mep72	↑	55.8
PA2783	1421	mep72	Metzincin protease Mep72	↑	21.6
PA1706	1483	pcrV	Type III secretion protein PcrV	↑	7.9
PA1094	810	fliD	Flagella capping protein FliD	↑	7.6
PA2783	880	mep72	Metzincin protease Mep72	↑	7.2
Spots displaying decreased abundance in the wild-type (PAO1) secretome
PA1709	1401	popD	Type III secretion protein PopD	↓	7.1
PA3841	757	exoS	Type III secretion effector ExoS	↓	5.1
PA3841/PA0044	751	exoS-exoT	Type III secretion effector ExoS/ExoT	↓	3.8

^aSummary of the identified protein spots modulated in the PAO1 secretome compared to their activity in the mep72 mutant secretome. While LC-MS/MS analysis identified spot 757 as ExoS, spot 751 was identified as either ExoS or ExoT. Given that ExoS and ExoT share 74% amino acid sequence homology, many of the peptide sequences retrieved following trypsin digestion are almost identical. In these circumstances, ExoS and ExoT cannot be distinguished from each other.

^b↑ and ↓ arrows indicate whether the spot was more or less abundant in the PAO1 secretome than in the mep72 mutant secretome.