TABLE 6.

Envelope and periplasmic genes

Gene	Function	Log2 pH ratioa			Classb
		5/7	8.7/7	8.7/5
artI	Periplasmic binding protein of Arg transport system	0.286	0.655	0.369	BH
artM	Arginine periplasmic binding protein	−0.115	0.293	0.407	BH
btuB	B-12 transporter, outer membrane receptor	−0.667	0.037	0.704	AL
cirA	Colicin I receptor production	−0.885	0.260	1.145	AL
clpX	ATPase subunit of ClpXP protease	−0.361	−0.625	−0.264	BL
cpxA	Periplasmic stress sensor (CpxAR)	−0.461	0.230	0.691	AL
cpxP	CpxAR-regulated periplasmic stress protein	−3.232	1.002	4.234	AL
cpxR	Periplasmic stress response regulator (CpxAR)	−0.662	0.590	1.251	AL
dsbA	Thiol:disulfide interchange, periplasmic	0.086	1.117	1.031	BH
dsbC	Disulfide bond isomerase, periplasmic chaperone	−0.288	−0.534	−0.246	BL
fadL	Fatty acid transport, outer membrane	−0.861	1.069	1.931	BH
fecA	Outer membrane ferric citrate receptor	−2.608	−1.128	1.480	NH
fecB	Periplasmic ferric citrate-binding protein	−2.842	−1.538	1.304	NH
fepA	Ferrienterobactin outer membrane receptor	−0.966	−0.289	0.676	NH
fhuD	Ferric hydroxamate binding protein; hydroxamate-dependent iron uptake	−0.767	−0.180	0.587	AL
fliY	Cystine-binding protein, periplasmic	0.233	−0.252	−0.484	AH
hdeA	Acid periplasmic chaperone	0.841	−0.326	−1.167	AH
hdeB	Acid periplasmic protein	0.782	−0.622	−1.404	AH
hisJ	High-affinity histidine-binding protein	−0.149	0.400	0.549	BH
hlpA	Periplasmic chaperone for OMPsc	0.099	−0.661	−0.759	BL
lamB	Maltoporin, maltose high-affinity uptake; phage lambda receptor	−4.881	−3.735	1.146	NH
lon	DNA-binding, ATP-dependent protease	−0.600	−1.666	−1.065	BL
malE	Maltose-binding protein, periplasmic	−3.425	−2.933	0.491	NH
malM	Maltose operon periplasmic protein	−4.643	−3.780	0.863	NH
mltB	Membrane-bound murein hydrolase	−0.739	−0.419	0.320	NH
nmpC	Outer membrane	−4.012	−0.051	3.961	AL
ompF	Outer membrane porin protein 1a	−2.834	−0.892	1.942	AL
ompT	Outer membrane protease VII	−0.815	−1.204	−0.389	BL
ompX	OMP, induces RNAP-sigma E	1.523	0.439	−1.083	NL
oppA	Periplasmic oligopeptide binding protein	1.358	0.406	−0.953	NL
pal	Lipoprotein associated with peptidoglycan	0.532	0.379	−0.153	NL
potD	Spermidine-binding membrane protein; regulates pot	0.053	0.509	0.456	BH
ppiA	Rotamase; peptidylprolyl-cis-trans-isomerase A	−0.526	0.231	0.757	AL
pstS	High-affinity, periplasmic phosphate binding protein	−2.479	−2.262	0.217	NH
rbsB	d-Ribose binding protein, periplasmic	−0.749	−1.150	−0.401	BL
rseB	Periplasmic, binds RseA; enhances RpoE-RseA cytoplasmic complex formation	0.631	−0.105	−0.736	AH
secD	SecDF-YajC inner membrane secretion complex	−0.165	0.287	0.452	AL
surA	Periplasmic outer membrane porin chaperone, stationary phase	0.310	0.209	−0.101	NL
tatA	Twin arginine translocation	0.043	0.679	−0.636	BH
tatB	Twin arginine translocation	0.075	0.446	0.372	BH
tolB	Group A colicin uptake and tolerance	0.498	0.421	−0.077	NL
tpX	Thiol peroxidase, antioxidant	0.637	0.178	−0.459	NL
tsx	Phage T6, colicin K resistance; nucleoside channel	−0.707	−0.904	−0.196	BL
ybgF	TolA-binding periplasmic protein	0.312	−0.007	−0.318	AH
yceI	Function unknown; periplasmic protein	−0.036	1.038	1.074	BH
yhcN	Periplasmic protein	3.064	−1.136	−4.199	AH

^aValues in boldface indicate significance (α = 0.001).

^bAH, Acid High; AL, Acid Low; BH, Base High; BL, Base Low; NH, Neutral High; NL, Neutral Low.

^cOMPs, outer membrane proteins.

^dRNAP, RNA polymerase.