Table 2.

Estimation of subproteome study error rate.

Organism	Fractiona)	Total proteins identified	Disagreementsb)	Confirmed PSORTb errorsc)	Confirmed laboratory errorsd)	% Errorse)
E. coli [64]	C	23	1	0	0	0.0
Synechocystis [15]	CM	63	25	0	4	6.3
Synechocystis [46]	P	57	5	0	1	1.8
K. pneumoniae [16]	OM	3	0	0	0	0.0
S. typhimurium [16]	OM	11	2	0	2	18.2
E. coli [17]	OM	39	8	0	6	15.4
P. gingivalis [18]	OM	6	1	0	1	16.7
P. aeruginosa [13]	OM	33	6	0	3	9.1
P. aeruginosa [13]	EC	150	81	2	36	24.0
H. pylori [19]	EC	20	9	1	5	25.0
Total		405	138	3	58	14.3

^a) C = cytoplasmic, CM = cytoplasmic membrane, P = periplasmic, OM = outer membrane, and EC = extracellular.

^b) Disagreement represents the number of proteins of the fraction X predicted by PSORTb not to be resident at X or X/Y localization sites.

^c) Confirmed PSORTb error represents the number of disagreeing cases for which the PSORTb predicted localization site was found to be incorrect.

^d) Confirmed laboratory error represents the number of disagreeing cases for which the PSORTb predicted localization site was found to be correct.

^e) % Errors is calculated as the number of confirmed laboratory errors divided by the total number of proteins identified.