| CRISPR-associated endonuclease Cpf1 (EC 3.1.-.-) (FnCpf1) | cpf1 FTN_1397 | A0Q7Q2 | 1 |
| CRISPR-associated protein Csy3 | csy3 csy1-3 PA14_33310 | Q02MM1 | 1 |
| Cryptic nitrate reductase 2, alpha subunit | narZ SSON_1657 | Q3Z1L1 | 1 |
| CsuE | csuE | Q6XBY2 | 1 |
| CTP synthase (EC 6.3.4.2) (Cytidine 5'-triphosphate synthase) (Cytidine triphosphate synthetase) (CTP synthetase) (CTPS) (UTP--ammonia ligase) | pyrG ctrA MW2051 | P65924 | 1 |
| CTP synthase (EC 6.3.4.2) (Cytidine 5'-triphosphate synthase) (Cytidine triphosphate synthetase) (CTP synthetase) (CTPS) (UTP--ammonia ligase) | pyrG jhp_0323 | Q9ZM99 | 1 |
| CTP synthase (EC 6.3.4.2) (Cytidine 5'-triphosphate synthase) (Cytidine triphosphate synthetase) (CTP synthetase) (CTPS) (UTP--ammonia ligase) | pyrG spr0438 | Q8DQY0 | 1 |
| CTP synthase (EC 6.3.4.2) (Cytidine 5'-triphosphate synthase) (Cytidine triphosphate synthetase) (CTP synthetase) (CTPS) (UTP--ammonia ligase) | pyrG b2780 JW2751 | P0A7E5 | 1 |
| CTP synthase (EC 6.3.4.2) (Cytidine 5'-triphosphate synthase) (Cytidine triphosphate synthetase) (CTP synthetase) (CTPS) (UTP--ammonia ligase) | pyrG SPy_1894 M5005_Spy1610 M5005_Spy1609 | P65925 | 1 |
| CTP synthase (EC 6.3.4.2) (Cytidine 5'-triphosphate synthase) (Cytidine triphosphate synthetase) (CTP synthetase) (CTPS) (UTP--ammonia ligase) | pyrG SAOUHSC_02368 | Q2FWD1 | 1 |
| Cu(I)-translocating P-type ATPase | copA KPN_00464 | A6T5P4 | 1 |
| Curli production assembly/transport component CsgF | VSAK1_16577 | A6CUM6 | 1 |
| Curli production assembly/transport component CsgG | VSAK1_16582 | A6CUM7 | 1 |
| Curli production assembly/transport component CsgG family protein | HPSD74_1610 | U4SDH3 | 1 |
| Curli production assembly/transport component CsgG family protein | KW89_2690 | A0A0K2E057 | 1 |
| Curli production assembly/transport component, 2nd curli operon | csgG SSON_1046 | Q3Z389 | 1 |
| CvpA family protein | LMRG_00676 | A0A0H3GBG0 | 1 |
| Cwp13 (N-acetylmuramoyl-L-alanine amidase LytC) (EC 3.5.1.28) | cwp13 lytC_25 SAMEA3374989_02948 | L7PG66 | 1 |
| Cyanophycin synthetase | Fphi_1494 | B0TYX3 | 1 |
| Cyanophycin synthetase (EC 6.-.-.-) | cphA FTT_1130c | Q5NFT9 | 1 |
| Cyclic AMP receptor protein | crp KPN_03743 | A6TEZ6 | 1 |
| Cyclic di-GMP-binding protein (Cellulose synthase regulatory subunit) | bcsB yhjN b3532 JW3500 | P37652 | 1 |
| Cyclic nucleotide-binding domain protein | MXAN_6248 | Q1CYZ6 | 1 |
| Cyclic nucleotide-binding domain protein | MXAN_6249 | Q1CYZ5 | 1 |
| Cyclic pyranopterin monophosphate synthase (EC 4.6.1.17) (Molybdenum cofactor biosynthesis protein C) | moaC Plav_3176 | A7HXZ9 | 1 |
| Cyclic pyranopterin monophosphate synthase (EC 4.6.1.17) (Molybdenum cofactor biosynthesis protein C) | moaC VSAK1_03690 | A6D3S6 | 1 |
| Cyclopropane fatty acid synthase, methyltransferase | cfa FTN_1456 | A0Q7V9 | 1 |
| Cyclopropane mycolic acid synthase 2 (CMAS) (EC 2.1.1.79) (Cyclopropane-fatty-acyl-phospholipid synthase) (CFA synthase) (Cyclopropane fatty acid synthase) (Mycolic acid methyltransferase) (MA-MT) (S-adenosylmethionine-dependent methyltransferase) (AdoMet-MT) (SAM-MT) | cmaA2 cma2 CMAS-2 Rv0503c MTCY20G9.30c | P9WPB5 | 1 |
| Cyclopropane-fatty-acyl-phospholipid synthase | B195_01210 | M5R4I3 | 1 |
| CylM protein, cytolytic toxin system | cylM spr1767 | Q8DNF6 | 1 |
| Cys-tRNA(Pro)/Cys-tRNA(Cys) deacylase (EC 4.2.-.-) | SPy_0599 | Q9A0V4 | 1 |
| Cystathionine beta-lyase (EC 4.4.1.8) | VSAK1_01262 | A6D2D8 | 1 |
| Cystathionine gamma-synthase (CGS) (EC 2.5.1.48) (O-succinylhomoserine (thiol)-lyase) | metB Rv1079 MTV017.32 | P9WGB7 | 1 |
| Cystathionine gamma-synthase (CGS) (O-succinylhomoserine(Thiol)-lyase) (EC 2.5.1.48) | SP70585_1564 | C1C8B6 | 1 |
| Cystathionine gamma-synthase (EC 2.5.1.48) | VSAK1_09473 | A6D0D5 | 1 |
| Cysteine desulfurase (EC 2.8.1.7) | SPy_0288 | Q9A1G3 | 1 |
| Cysteine desulfurase (EC 2.8.1.7) | sufS KW89_1440 | A0A0B8UQE6 | 1 |
| Cysteine desulfurase IscS (EC 2.8.1.7) | iscS CPC_2029 | B1BJ74 | 1 |
| Cysteine desulfurase IscS (EC 2.8.1.7) | iscS SC1083_0170 | G4A5T5 | 1 |
| Cysteine desulfurase IscS (EC 2.8.1.7) | yfhO iscS SSON_2612 | Q3YZ22 | 1 |
| Cysteine desulfurase IscS (EC 2.8.1.7) | iscS HPSD74_0331 | U4SJA7 | 1 |
| Cysteine desulfurase IscS (EC 2.8.1.7) | iscS_2 iscS SAMEA3374989_02403 SAMEA3375059_02465 | A0A160WY74 | 1 |
| Cysteine desulfurase IscS (EC 2.8.1.7) | iscS SCH_2537 | Q57LG9 | 1 |
| Cysteine desulfurase IscS (EC 2.8.1.7) (NifS protein homolog) (ThiI transpersulfidase) (TusA transpersulfidase) | iscS nuvC yfhO yzzO b2530 JW2514 | P0A6B7 | 1 |
| Cysteine synthase | cysK FTN_1302 | A0Q7G8 | 1 |
| Cysteine synthase (EC 2.5.1.47) | cysK AC1_1717 | B1RCB1 | 1 |
| Cysteine synthase (EC 2.5.1.47) | cysK PA2709 | Q9I0D3 | 1 |
| Cysteine synthase (EC 2.5.1.47) | cysK YPO2992 | Q7CJF5 | 1 |
| Cysteine synthase (EC 2.5.1.47) | cysK cysK_1 AGG09_21630 BB749_07505 BCB67_11260 BL143_04905 PMK1_00258 SAMEA3531778_01627 SM57_03014 | Q0ZB89 | 1 |
| Cysteine synthase (EC 2.5.1.47) | cysK HPSD74_2038 | U4SAY8 | 1 |
| Cysteine synthase (EC 2.5.1.47) | cysK SCH_2428 | Q57LS8 | 1 |
| Cysteine synthase (EC 2.5.1.47) | SAOUHSC_00488 | Q2G0Q8 | 1 |
| Cysteine synthase A | SC1083_1109 | G4A8G1 | 1 |
| Cysteine synthase B (CSase B) (EC 2.5.1.47) (O-acetylserine (thiol)-lyase B) (OAS-TL B) (O-acetylserine sulfhydrylase B) | cysM Cj0912c | P71128 | 1 |
| Cysteine--tRNA ligase (EC 6.1.1.16) (Cysteinyl-tRNA synthetase) (CysRS) | cysS Fphi_0516 | B0U0I3 | 1 |
| Cysteine--tRNA ligase (EC 6.1.1.16) (Cysteinyl-tRNA synthetase) (CysRS) | cysS spr0519 | Q8DQS8 | 1 |
| Cysteine--tRNA ligase (EC 6.1.1.16) (Cysteinyl-tRNA synthetase) (CysRS) | cysS PA1795 | Q9I2U7 | 1 |
| Cysteine--tRNA ligase (EC 6.1.1.16) (Cysteinyl-tRNA synthetase) (CysRS) | cysS SFV_0484 | Q0T776 | 1 |
| Cysteine--tRNA ligase (EC 6.1.1.16) (Cysteinyl-tRNA synthetase) (CysRS) | cysS SPy_1941 M5005_Spy1655 | Q99XZ9 | 1 |
| Cysteine-rich repeat protein | MXAN_1733 | Q1DBJ0 | 1 |
| Cysteine/glutathione ABC transporter membrane/ATP-binding component (EC 3.6.3.44) | OOM_1225 | I2AZQ1 | 1 |
| Cytidylate kinase (CK) (EC 2.7.4.25) (Cytidine monophosphate kinase) (CMP kinase) | cmk FTN_0956 | A0Q6H9 | 1 |
| Cytochrome b | petB PP_1318 | Q88N94 | 1 |
| Cytochrome b561 | PP_2010 | Q88LC5 | 1 |
| Cytochrome b562 family protein | HPSD74_2051 | U4S9Z6 | 1 |
| Cytochrome bd ubiquinol oxidase subunit 2 (EC 1.10.3.-) (Cytochrome d ubiquinol oxidase subunit II) | cydB yxkL BSU38750 | P94365 | 1 |
| Cytochrome bd ubiquinol oxidase subunit I | SC1083_1311 | G4A905 | 1 |
| Cytochrome bd-II terminal oxidase subunit I | appC FTN_1619 | A0Q8B3 | 1 |
| Cytochrome bo(3) ubiquinol oxidase subunit 2 (Cytochrome b562-o complex subunit II) (Cytochrome o ubiquinol oxidase subunit 2) (Cytochrome o subunit 2) (Oxidase bo(3) subunit 2) (Ubiquinol oxidase chain B) (Ubiquinol oxidase polypeptide II) (Ubiquinol oxidase subunit 2) | cyoA b0432 JW0422 | P0ABJ1 | 1 |
| Cytochrome c biogenesis ATP-binding export protein CcmA (EC 3.6.3.41) (Heme exporter protein A) | ccmA VSAK1_03174 | A6CXC7 | 1 |
| Cytochrome c oxidase subunit (Cbb3-type) | PA4133 | Q9HWP8 | 1 |
| Cytochrome c oxidase subunit 1 (EC 1.9.3.1) | ctaD PP_0104 | Q88RM5 | 1 |
| Cytochrome c oxidase subunit 2 (EC 1.9.3.1) | PP_0103 | Q88RM6 | 1 |
| Cytochrome c oxidase subunit 2 (EC 1.9.3.1) (Caa-3605 subunit 2) (Cytochrome aa3 subunit 2) (Cytochrome c oxidase polypeptide II) (Oxidase aa(3) subunit 2) | ctaC BSU14890 | P24011 | 1 |
| Cytochrome c oxidase subunit I, cbb3-type (EC 1.9.3.1) | ccoN-II PP_4255 | Q88F44 | 1 |
| Cytochrome c oxidase, subunit III (EC 1.9.3.1) | coxC MXAN_6088 | Q1CZF0 | 1 |
| Cytochrome c-552 (EC 1.7.2.2) | nrfA Cj1357c | Q0P8Q2 | 1 |
| Cytochrome c-553 (Cytochrome c553) | jhp_1148 | Q9ZJZ9 | 1 |
| Cytochrome c-type biogenesis protein CcmE (Cytochrome c maturation protein E) (Heme chaperone CcmE) | ccmE cycJ PP_4323 | Q88EX9 | 1 |
| Cytochrome c-type biogenesis protein CcmE (Cytochrome c maturation protein E) (Heme chaperone CcmE) | ccmE cycJ PA1479 | Q9I3N3 | 1 |
| Cytochrome c-type biogenesis protein CcmE (Cytochrome c maturation protein E) (Heme chaperone CcmE) | ccmE cycJ HPSD74_2113 | U4SB69 | 1 |
| Cytochrome c-type biogenesis protein CcmE (Cytochrome c maturation protein E) (Heme chaperone CcmE) | ccmE cycJ VSAK1_03194 | A6CXD1 | 1 |
| Cytochrome c-type biogenesis protein CcmF | VSAK1_03199 | A6CXD2 | 1 |
| Cytochrome c-type biogenesis protein CcmH | ccmH PA1482 | Q9I3N0 | 1 |
| Cytochrome c-type protein TorC | torC b0996 JW0981 | P33226 | 1 |
| Cytochrome c-type protein TorY | torY yecK b1873 JW1862 | P52005 | 1 |
| Cytochrome c5 | NMB1677 | Q9JYA2 | 1 |
| Cytochrome C551 peroxidase (EC 1.11.1.5) | Cj0020c | Q0PCA5 | 1 |
| Cytochrome d terminal oxidase polypeptide subunit I | cydA SSON_0685 | Q3Z471 | 1 |
| Cytochrome d terminal oxidase polypeptide subunit I (Cytochrome d terminal oxidase, polypeptide subunit I) | cydA ECs0768 Z0900 | Q8X979 | 1 |
| Cytochrome d terminal oxidase polypeptide subunit II | cydB SCH_0745 | Q57RL0 | 1 |
| Cytochrome d terminal oxidase, polypeptide subunit I | cydA SCH_0744 | Q57RL1 | 1 |
| Cytochrome d terminal oxidase, polypeptide subunit I (EC 1.10.3.-) | cydA FTT_0279c | Q5NI13 | 1 |
| Cytochrome d ubiquinol oxidase subunit I | OOM_0172 | I2AX34 | 1 |
| Cytochrome d ubiquinol oxidase, subunit I, putative | SAOUHSC_01031 | Q2FZH3 | 1 |
| Cytochrome d ubiquinol oxidase, subunit II, putative (EC 1.10.3.-) | SAOUHSC_01032 | Q2FZH2 | 1 |
| Cytochrome o ubiquinol oxidase subunit I | cyoB SCH_0484 | Q57SC1 | 1 |
| Cytochrome O ubiquinol oxidase subunit I (EC 1.10.3.-) | cyoB FTT_0282 | Q5NI10 | 1 |
| Cytochrome o ubiquinol oxidase, subunit I | VSAK1_06660 | A6D1U0 | 1 |
| Cytochrome oxidase (CBB3-TYPE) | fixN jhp_0132 | Q9ZMT6 | 1 |