The human urinary proteome contains more than 1500 proteins, including a large proportion of membrane proteins

Table 1 Experimental conditions and statistics on database searches of four individual experiments using a single urine sample

	In-gel 1	In-gel 2	In-solution 1	In-solution 2
Urinary protein	150 μg	150 μg	125 μg	125 μg
Albumin removal	-	-	+	+
Protein separation	Invitrogen NuPAGE 4-12% Bis-Tris 1D gel		Agilent mRP-C18 column
Number of fraction	14	10	22	22
Digestion	In-gel	In-gel	In-solution	In-solution
Denaturant			50% Trifluoroethanol	6 mol/l Urea + 2 mol/l thiourea
LC gradient time	100 min	140 min	100 min	100 min
Identified IT-MS² spectra by Mascot^a	16,219	10,535	13,367	10,175
Number of unique peptides^a	4504	3853	3164	2637
Number of identified proteins^a	759	815	656	580
Total number of unique peptides^a	8041
Total number of identified proteins^a	1281

^aApplied criteria are described in the Materials and methods section. 1D, one-dimensional; LC, liquid chromatography; MS, mass spectrometry.

ISSN: 1474-760X