Table 2.

Small ORFs (<15 kDa) with no assigned function, which are highly conserved in Brucella species.

B. abortus 2308 ORFa	B. suis 1330 ORFa	B. melitensis 16M ORFa	Annotationb	In vitro CIc	In vivo CId
BAB2_0068e	BRA0069	BMEII0025	Type IV secretion system protein virB1	0.0023	0.0001
BAB1_0061	BR0064	BMEI1881	hypothetical protein	0.7493	1.2039
BAB1_0355	BR0325	BMEI1597	COG1380 LrgA family protein [general function prediction only]	1.3655	0.0153
BAB1_0513	BR0488	BMEI1447	hypothetical protein	5.6537	1.0448
BAB1_0581	BR0557	BMEI1376	COG3654; prophage maintenance system killer protein [general function prediction only]	1.8387	0.5577
BAB1_0626	BR0602	BMEI1339	hypothetical protein	3.6877	N
BAB1_0743	BR0725	BMEI1227	hypothetical protein [possible relationship to acetyltransferases]	0.6340	0.6160
BAB1_0992	BR0973	BMEI1005	hypothetical protein	1.1191	0.4853
BAB1_1106	BR1083	BMEI0899	COG3617; prophage antirepressor [possible function in transcription]	1.2815	0.6963
BAB1_1194	BR1173	BMEI0813	hypothetical protein	1.2322	0.3799
BAB1_1204	BR1181	BMEI0806	hypothetical protein	1.3258	0.4248
BAB1_1262	BR1241	BMEI0751	hypothetical protein	N	1.5608
BAB1_1390	BR1370	BMEI0633	COG0239; possible integral membrane protein	N	1.8630
BAB1_1392	BR1372	BMEI0631	COG3467; predicted flavin nucleotide binding protein [general function prediction only]	N	1.4038
BAB1_1743	BR1730	BMEI0308	hypothetical protein	0.6744	N
BAB1_1748	BR1736	BMEI0304	COG1607, Acyl-CoA hydrolase [Lipid metabolism]	N	1.3140
BAB1_1939	BR1938	BMEI0127	hypothetical protein	0.4634	0.4569
BAB1_2041	BR2041	BMEI0030	DUF188 superfamily	2.6421	0.5280
BAB2_0160	BRA0162	BMEII1078	COG4893; uncharacterized protein conserved in bacteria	0.6152	1.1670
BAB2_0170	BRA0175	BMEII1067	DUF465 superfamily; putative cytosolic protein	0.2584	N
BAB2_0761	BRA0476	BMEII0789	hypothetical protein	0.5177	N
BAB2_0726	BRA0512	BMEII0758	Pfam01873; YbgT-like protein	0.0079	0.0001
BAB2_0470	BRA0769	BMEII0522	Pfam05635; family of hypothetical proteins	0.0002	0.0025
BAB2_0450	BRA0787	BMEII0503	hypothetical protein	0.0435	0.0180
BAB2_0415	BRA0819	BMEII0468	hypothetical protein	1.0595	1.2254
BAB2_0400	BRA0836	BMEII0454	hypothetical protein	1.0501	1.8400
BAB2_0232	BRA1000	BMEII0296	hypothetical protein	N	0.9205
BAB2_1072	BRA1113	BMEII0186	pemK family protein [possible regulator]	5.1792	0.5605
BAB2_1087	BRA1130	BMEII0169	Hypothetical protein [flagellar locus]	N	1.0841
BAB2_1136	BRA1177	BMEII0118	DUF1634 superfamily	0.2300	0.4828

^aORF number from NCBI.

^bFollowed B. suis 1330 assignment.

^cCompetitive index (CI): Calculated as Mean Mutants/WT from at least three experiments. N: Not tested.

^dCompetitive index (CI): Calculated as Mean Mutants/WT in spleen of 2–5 mice. N: Not tested.

^eA previously characterized virB1 mutant (BA41) serves as attenuation phenotype control.