TABLE 2.

Protein identifications for experimental control mixture

No.	Protein	Accession no.a	Mol wt	Concn (nM)	Identifi- cationb
1	Bovine beta-casein	P02666	25,107	100	+
2	Bovine carbonic anhydrase	P00921	28,980	100	+
3	Bovine serum albumin	P02769	69,293	40	+
4	Bovine beta-lactoglobulin	P02754	19,883	20	+
5	E. coli alkaline phosphatase	P00634	49,438	20	+
6	Bovine serotransferrin	Q29443	77,753	10	+
7	Rabbit GAPDHc	P46406	35,688	2	+
8	Bovine catalase	P00432	57,585	2	+
9	Rabbit glycogen phosphorylase	P00489	97,158	1	+
10	Bovine cytochrome c	P00006	11,572	40	−
11	E. coli beta-galactosidase	P00722	116,351	0.4	−
12	Bovine alpha-lactalbumin	P00711	16,246	10	−
13	Bacillus lichenformis alpha-amylase	Q04977	66,924	4	−
14	Horse myoglobin	P02188	16,951	4	−
15	Saccharomyces cerevisiae mannose-6-phosphate isomerase	P29952	48,057	1	−
16	Chicken ovalbumin	P01012	42,750	0.4	−
17	Bovine gamma-actin	ATBOG	41,661	0.2	−
18	Rabbit myosin	P02562	241,852	0.2	−

^aMost protein accession numbers are from the SWISS-PROT database (http://www.expasy.org/sprot); the only exception is the accession number of bovine gamma-actin, which is from the PIR database (http://pir.georgetown.edu).

^bProteins 1 through 9 were identified with high confidence (see Table 1) and were subsequently confirmed manually.

^cGAPDH, glyceraldehyde-3-phosphate dehydrogenase.