| Urease subunit gamma (EC 3.5.1.5) (Urea amidohydrolase subunit gamma) | ureA Rv1848 MTCY359.25c | P9WFE7 | 1 |
| Uridine kinase (EC 2.7.1.48) (Cytidine monophosphokinase) (Uridine monophosphokinase) | udk SPy_1368 M5005_Spy1116 | P67415 | 1 |
| Uridine phosphorylase | Fphi_0169 | B0TYM5 | 1 |
| Uridine phosphorylase | udp FTN_0652 | A0Q5M9 | 1 |
| Uridine phosphorylase (EC 2.4.2.3) | udp YPO3786 | Q0WAM5 | 1 |
| Uridine phosphorylase (EC 2.4.2.3) | udp S3845 SF3909 AJR25_008985 AJR27_003425 | Q83PG8 | 1 |
| Uridine phosphorylase (EC 2.4.2.3) | udp SPy_1869 | Q99Y49 | 1 |
| Uridine phosphorylase (EC 2.4.2.3) | udp SCH_3866 | Q57HP0 | 1 |
| Uridine phosphorylase (UPase) (UrdPase) (EC 2.4.2.3) | udp STM3968 STMD1.21 | P0A1F6 | 1 |
| Uridylate kinase (UK) (EC 2.7.4.22) (Uridine monophosphate kinase) (UMP kinase) (UMPK) | pyrH Fphi_0596 | B0U0Z9 | 1 |
| Uridylate kinase (UK) (EC 2.7.4.22) (Uridine monophosphate kinase) (UMP kinase) (UMPK) | pyrH FTN_0229 | A0Q4H3 | 1 |
| Uridylate kinase (UK) (EC 2.7.4.22) (Uridine monophosphate kinase) (UMP kinase) (UMPK) | pyrH CPR_1670 | Q0SSC2 | 1 |
| Uridylate kinase (UK) (EC 2.7.4.22) (Uridine monophosphate kinase) (UMP kinase) (UMPK) | pyrH spr0845 | Q8DQ50 | 1 |
| Uridylate kinase (UK) (EC 2.7.4.22) (Uridine monophosphate kinase) (UMP kinase) (UMPK) | pyrH SPy_0462 M5005_Spy0377 M5005_Spy0378 M5005_Spy0379 | P65938 | 1 |
| Uridylate kinase (UK) (EC 2.7.4.22) (Uridine monophosphate kinase) (UMP kinase) (UMPK) | pyrH CD630_21380 | Q185S7 | 1 |
| Uridylate kinase (UK) (EC 2.7.4.22) (Uridine monophosphate kinase) (UMP kinase) (UMPK) | pyrH SAOUHSC_01235 | Q2FZ22 | 1 |
| Urocanate hydratase (Urocanase) (EC 4.2.1.49) (Imidazolonepropionate hydrolase) | hutU B195_02443 | M5R380 | 1 |
| Urocanate hydratase (Urocanase) (EC 4.2.1.49) (Imidazolonepropionate hydrolase) | hutU MXAN_4343 | Q1D4A7 | 1 |
| Urocanate hydratase (Urocanase) (EC 4.2.1.49) (Imidazolonepropionate hydrolase) | hutU KPR_3792 | R4YCT2 | 1 |
| Urocanate hydratase (Urocanase) (EC 4.2.1.49) (Imidazolonepropionate hydrolase) | hutU SAOUHSC_02607 | Q2FVT5 | 1 |
| Uroporphyrinogen decarboxylase (UPD) (URO-D) (EC 4.1.1.37) | hemE FTN_1664 | A0Q8F6 | 1 |
| Uroporphyrinogen decarboxylase (UPD) (URO-D) (EC 4.1.1.37) | hemE BSU10120 | P32395 | 1 |
| Uroporphyrinogen III methylase | hemX SCH_3837 | Q57HR9 | 1 |
| Uroporphyrinogen III methylase | KU39_131 | A0A0K2KZS9 | 1 |
| UTP--glucose-1-phosphate uridylyltransferase (EC 2.7.7.9) (Alpha-D-glucosyl-1-phosphate uridylyltransferase) (UDP-glucose pyrophosphorylase) (UDPGP) (Uridine diphosphoglucose pyrophosphorylase) | galU ychD b1236 JW1224 | P0AEP3 | 1 |
| UTP--glucose-1-phosphate uridylyltransferase (EC 2.7.7.9) (Alpha-D-glucosyl-1-phosphate uridylyltransferase) (UDP-glucose pyrophosphorylase) (UDPGP) (Uridine diphosphoglucose pyrophosphorylase) | galF wcaN b2042 JW2027 | P0AAB6 | 1 |
| UTP--glucose-1-phosphate uridylyltransferase (EC 2.7.7.9) (UDP-glucose pyrophosphorylase) | galU NMB0638 | Q9K0G7 | 1 |
| UTP--glucose-1-phosphate uridylyltransferase (EC 2.7.7.9) (UDP-glucose pyrophosphorylase) | galU spr1903 | Q8DN58 | 1 |
| UTP--glucose-1-phosphate uridylyltransferase 1 (EC 2.7.7.9) (Alpha-D-glucosyl-1-phosphate uridylyltransferase 1) (UDP-glucose pyrophosphorylase 1) (UDPGP 1) (Uridine diphosphoglucose pyrophosphorylase 1) | hasC1 hasC SPy_2202 M5005_Spy1853 | P0C0I9 | 1 |
| UTP--glucose-1-phosphate uridylyltransferase 2 (EC 2.7.7.9) (Alpha-D-glucosyl-1-phosphate uridylyltransferase 2) (UDP-glucose pyrophosphorylase 2) (UDPGP 2) (Uridine diphosphoglucose pyrophosphorylase 2) | hasC2 hasC.2 SPy_0224 M5005_Spy0192 | P67068 | 1 |
| UvrABC system protein A (UvrA protein) (Excinuclease ABC subunit A) | uvrA Fphi_0155 | B0TYL1 | 1 |
| UvrABC system protein A (UvrA protein) (Excinuclease ABC subunit A) | uvrA spr0171 | P63385 | 1 |
| UvrABC system protein A (UvrA protein) (Excinuclease ABC subunit A) | uvrA dinE b4058 JW4019 | P0A698 | 1 |
| UvrABC system protein A (UvrA protein) (Excinuclease ABC subunit A) | uvrA BSU35160 | O34863 | 1 |
| UvrABC system protein A (UvrA protein) (Excinuclease ABC subunit A) | uvrA SPy_1825 M5005_Spy1550 | Q99Y84 | 1 |
| UvrABC system protein A (UvrA protein) (Excinuclease ABC subunit A) | uvrA LMRG_01760 | A0A0H3GKC7 | 1 |
| UvrABC system protein B (Protein UvrB) (Excinuclease ABC subunit B) | uvrB PA3138 | P72174 | 1 |
| UvrABC system protein B (Protein UvrB) (Excinuclease ABC subunit B) | uvrB SPy_1314 M5005_Spy1075 | Q99ZA5 | 1 |
| V-type ATP synthase alpha chain (EC 3.6.3.14) (V-ATPase subunit A) | atpA ntpA SPy_0154 M5005_Spy0131 | Q9A1Q3 | 1 |
| V-type ATP synthase beta chain (V-ATPase subunit B) | atpB CJD_2210 | B1V4X3 | 1 |
| V-type ATP synthase subunit I | CPC_1882 | B1BG75 | 1 |
| V-type ATPase, C subunit | AC3_2117 | B1BVX4 | 1 |
| V-type sodium ATPase, E subunit (EC 3.6.3.14) | atpE FSU_0091 | C9RNV0 | 1 |
| VacJ family lipoprotein | B195_20240 | M5QU88 | 1 |
| VacJ family lipoprotein | B195_15262 | M5QTB6 | 1 |
| VacJ like lipoprotein | OOM_0305 | I2AXF6 | 1 |
| Valine--tRNA ligase (EC 6.1.1.9) (Valyl-tRNA synthetase) (ValRS) | valS Fphi_0617 | B0U120 | 1 |
| Valine--tRNA ligase (EC 6.1.1.9) (Valyl-tRNA synthetase) (ValRS) | valS B195_05521 | M5R2P1 | 1 |
| Valine--tRNA ligase (EC 6.1.1.9) (Valyl-tRNA synthetase) (ValRS) | valS spr0492 | Q8DQU7 | 1 |
| Valine--tRNA ligase (EC 6.1.1.9) (Valyl-tRNA synthetase) (ValRS) | valS YPO3443 y0743 YP_0641 | Q8ZBH1 | 1 |
| Valine--tRNA ligase (EC 6.1.1.9) (Valyl-tRNA synthetase) (ValRS) | valS Rv2448c MTV008.04c | P9WFS9 | 1 |
| Valine--tRNA ligase (EC 6.1.1.9) (Valyl-tRNA synthetase) (ValRS) | valS b4258 JW4215 | P07118 | 1 |
| Valine--tRNA ligase (EC 6.1.1.9) (Valyl-tRNA synthetase) (ValRS) | valS SSON_4443 | Q3YU91 | 1 |
| Valine--tRNA ligase (EC 6.1.1.9) (Valyl-tRNA synthetase) (ValRS) | valS SPy_1568 M5005_Spy1292 | Q99YS1 | 1 |
| VanW-related protein | AC3_1588 | B1BRF1 | 1 |
| Vegetative catalase (EC 1.11.1.6) | katA kat kat-19 BSU08820 | P26901 | 1 |
| Vegetative protein 296 (VEG296) | sufC yurY BSU32710 | P80866 | 1 |
| Vibriobactin receptor | viuA VC_2211 | P0C6R1 | 1 |
| Vibriobactin receptor | viuA VS_1121 | B7VMJ7 | 1 |
| Vibrioferrin receptor | VS_II1127 | B7VSA7 | 1 |
| VirB10 type IV secretion protein | virB10 NSU_pLA2019 | G6ELE5 | 1 |
| VirB9 type IV secretion protein | virB9 NSU_pLA2018 | G6ELE4 | 1 |
| Virulence transcriptional regulatory protein PhoP | phoP SL1344_1169 | E1WFA1 | 1 |
| Virulence transcriptional regulatory protein PhoP | phoP SCH_1182 | Q57QC3 | 1 |
| Virulence-related outer membrane protein | ETAE_2675 | D0ZCH1 | 1 |
| Vitamin B12 transporter BtuB (Cobalamin receptor) (Outer membrane cobalamin translocator) | btuB KPN_04255 | A6TGF0 | 1 |
| Vitamin B12 transporter BtuB (Cobalamin receptor) (Outer membrane cobalamin translocator) | btuB VC_0156 | Q9KVI9 | 1 |
| Vitamin B12 transporter BtuB (Cobalamin receptor) (Outer membrane cobalamin translocator) | btuB VS_2998 | B7VM87 | 1 |
| Voltage-gated chloride channel | MXAN_0978 | Q1DDN4 | 1 |
| Voltage-gated chloride channel family protein | AC1_1808 | B1R6Q6 | 1 |
| von Willebrand factor type A domain protein | PG_0182 | Q7MXJ9 | 1 |
| von Willebrand factor type A domain protein | KW89_1962 | A0A0K2DYN1 | 1 |
| von Willebrand factor type A domain-containing protein | NSU_1365 | G6EAG7 | 1 |
| VRR-NUC domain protein | HMPREF1123_03653 | G6BNR2 | 1 |
| WD domain G-beta repeat protein | MXAN_3792 | Q1D5U9 | 1 |
| WD domain, G-beta repeat family protein | KW89_426 | A0A0K2DU62 | 1 |
| Wzc | wzc | A0A0H4UQY0 | 1 |
| X-prolyl aminopeptidase 2 | FTN_1074 | A0Q6U6 | 1 |
| Xaa-Pro aminopeptidase | VSAK1_24279 | A6D6K4 | 1 |
| Xaa-Pro dipeptidase | SP70585_0249 | C1CAJ6 | 1 |
| Xaa-Pro dipeptidase (X-Pro dipeptidase) (EC 3.4.13.9) (Imidodipeptidase) (Proline dipeptidase) (Prolidase) | pepQ YPO3765 y0465 YP_3283 | Q0WAP4 | 1 |
| Xaa-Pro dipeptidyl-peptidase (EC 3.4.14.11) (X-Pro dipeptidyl-peptidase) (X-prolyl-dipeptidyl aminopeptidase) (X-PDAP) | pepX pepXP SPy_1858 M5005_Spy1577 | Q99Y58 | 1 |
| Xanthine phosphoribosyltransferase (EC 2.4.2.22) (Xanthine-guanine phosphoribosyltransferase) (XGPRT) | gpt YPO3225 y0963 YP_0708 | Q8ZC05 | 1 |
| Xanthine phosphoribosyltransferase (XPRTase) (EC 2.4.2.22) | xpt SPP_1846 | C1CMF7 | 1 |
| Xanthine phosphoribosyltransferase (XPRTase) (EC 2.4.2.22) | xpt PA5298 | Q9HTQ6 | 1 |
| Xanthine phosphoribosyltransferase (XPRTase) (EC 2.4.2.22) | xpt SPy_1136 M5005_Spy0858 | Q99ZQ0 | 1 |
| Xanthine/uracil permease family protein | CPC_1994 | B1BFW2 | 1 |
| Xanthine/uracil permease family protein | CPC_1816 | B1BGE4 | 1 |
| Xanthine/uracil permease family/inorganic anion transporter, sulfate permease (SulP) family protein | Fphi_0482 | B0U071 | 1 |
| Xenobiotic reductase A | B195_05755 | M5QLQ0 | 1 |
| Xylanase-like protein | FSU_2795 | C9RKA3 | 1 |
| Xylanase/xylosidase | FSU_2274 | D9S442 | 1 |
| Xylanase/xylosidase (EC 3.2.1.8) | FSU_2269 | C9RS26 | 1 |
| YceI | NSU_0063 | G6E6U2 | 1 |
| YceI-like domain protein | NMH_1484 | E6MXS6 | 1 |
| YeeE/YedE family protein | CPC_0758 | B1BL07 | 1 |
| YfaZ | EDWATA_02770 | D4F7N4 | 1 |
| YngK protein | yngK-1 PG_0061 | Q7MXU6 | 1 |
| Zinc import ATP-binding protein ZnuC (EC 3.6.3.-) | znuC SSON_1283 | Q3Z2L6 | 1 |
| Zinc metalloprotease (EC 3.4.24.-) | AC1_2094 | B1RAG9 | 1 |