// NMR / fragment screening · Protein pipeline, Phase 6 evidence layer

Carbonic anhydrase 2

260 aa (P00918) · predicted structure regenerated live for this page (AlphaFold DB + ANM ensemble + fpocket + cross-frame ranker, same pipeline as every worked example on this site).

// Independently verified against a real PDB structure — not pipeline output

Independently checked against PDB 2CBA (catalytic zinc site). The rank-1 cluster (persistence 1.0) exactly matches the zinc-coordinating His94/His96/His119 triad plus four more real pocket-wall residues — a clean, correct hit on the second easy-case sanity anchor. Structural check: CA RMSD vs. 2CBA is 0.53 Å whole-chain, 0.29 Å within the pocket — the most accurate structural match in the batch.

Rank 1 Rank 2 Rank 3

// Sequence

MSHHWGYGKHNGPEHWHKDFPIAKGERQSPVDIDTHTAKYDPSLKPLSVSYDQATSLRILNNGHAFNVEFDDSQDKAVLKGGPLDGTYRLIQFHFHWGSLDGQGSEHTVDKKKYAAELHLVHWNTKYGDFGKAVQQPDGLAVLGIFLKVGSAKPGLQKVVDVLDSIKTKGKSADFTNFDPRGLLPESLDYWTYPGSLTTPPLLECVTWIVLKEPISVSSEQVLKFRKLNFNGEGEPEELMVDNWRPAQPLKNRQIKASFK
Length260 aa
UniProtP00918
Mean structure confidence0.9737
Pocket clusters3
Numbering cross-walk258/260 vs. 3K34

// Findings

Family, precedent, and provenance

Family classification

returned data

Carb_anhydrase (PF00194) — Eukaryotic-type carbonic anhydrase

E=1.40e-94 · bit score 317.2 · passes GA threshold: yes

Known ligand precedent

returned data

1429 total structures in family · 13 distinct ligand scaffolds curated

  • 3K34HGB, SUA
  • 5Y2SCO2
  • 6KLZBCT
  • 6ROBHG, BE7, KBZ, GLC, BGC
  • 6SBLHG, L4Q, BE7

Conservation

returned data

250 seed sequences · mean pairwise identity 31.3%

Similar known proteins

returned data
  • 3K34100.0% identity · HGB, SUA
  • 3KS3100.0% identity · (none)
  • 5Y2S100.0% identity · CO2
  • 4YXI100.0% identity · 4J8, MBO
  • 4FPT100.0% identity · 0VZ, MBO

Structure-based (Foldseek)

  • 1ZSC — TM 1.000 · 100% id (new vs. sequence list)
  • 5JE7 — TM 1.000 · 100% id (new vs. sequence list)
  • 3RYY — TM 1.000 · 100% id (new vs. sequence list)
  • 2H4N — TM 1.000 · 100% id (new vs. sequence list)
  • 6QL3 — TM 1.000 · 98% id (new vs. sequence list)

Interaction fingerprints (Evidence Integration Layer)

returned data

Representative complex: 3K34 (HGB, 0.90 Å)

Residue (PDB)Residue (pipeline)InteractionPartner
138137hydrophobicPRO138 (hydrophobic) with ligand HGB

Representative complex: 5Y2S (CO2, 0.90 Å)

Residue (PDB)Residue (pipeline)InteractionPartner
199198hydrogen bondTHR199 (hydrogen bond) with ligand CO2
200199water bridgeTHR200 (water bridge) with ligand CO2
200199water bridgeTHR200 (water bridge) with ligand CO2
9292water bridgeGLN92 (water bridge) with ligand CO2

Representative complex: 6KLZ (BCT, 0.90 Å)

Residue (PDB)Residue (pipeline)InteractionPartner
199198hydrogen bondTHR199 (hydrogen bond) with ligand BCT
119119hydrogen bondHIS119 (hydrogen bond) with ligand BCT
199198hydrogen bondTHR199 (hydrogen bond) with ligand BCT
9494water bridgeHIS94 (water bridge) with ligand BCT
200199water bridgeTHR200 (water bridge) with ligand BCT
9292water bridgeGLN92 (water bridge) with ligand BCT
9292water bridgeGLN92 (water bridge) with ligand BCT
9292water bridgeGLN92 (water bridge) with ligand BCT
9292water bridgeGLN92 (water bridge) with ligand BCT

Structural analysis — ranked pocket clusters

returned data

Residue numbers below are pipeline-sequential, with the literature (author-deposited PDB 3K34) number shown in parentheses — 258/260 residues cross-walked.

RankPersistenceResidues
#115(5), 7(7), 62(62), 64(64), 65(65), 67(67), 91(91), 92(92), 94(94), 96(96), 119(119), 121(121), 130(131), 134(135), 140(141), 142(143), 196(197), 197(198), 198(199), 199(200) …
#213(3), 4(4), 5(5), 6(6), 7(7), 8(8), 11(11), 63(63), 64(64), 169(170), 230(231), 231(232), 232(233), 235(236), 236(237), 238(239), 239(240), 241(242)
#313(3), 4(4), 5(5), 9(9), 10(10), 11(11), 15(15), 16(16), 18(18), 19(19), 20(20)

Pocket residues overlapping known interaction sites

  • Pocket 1: residues 92, 94, 119, 198, 199 (5 of 24 pocket residues match a known interaction site)
  • Pocket 2: no overlap with known interaction sites (18 checked)
  • Pocket 3: no overlap with known interaction sites (11 checked)

Pocket functional context (UniProt + ClinVar)

Pocket 1

  • Residue 7: SiteFine-tunes the proton-transfer properties of H-64
  • Residue 7: ClinVar variant [Pathogenic]Y7* (NM_000067.3(CA2):c.21C>A (p.Tyr7Ter))
  • Residue 62: SiteFine-tunes the proton-transfer properties of H-64; involved in the binding of some activators, including histamine and L-histidine
  • Residue 64: Active siteProton donor/acceptor
  • Residue 67: SiteFine-tunes the proton-transfer properties of H-64; involved in the binding of some activators, including histamine and L-histidine
  • Residue 92: SiteInvolved in the binding of some activators, including histamine and L-histidine
  • Residue 92: ClinVar variant [Likely pathogenic]Q92P (NM_000067.3(CA2):c.275A>C (p.Gln92Pro))
  • Residue 92: ClinVar variant [Likely pathogenic]Y92* (NM_000067.3(CA2):c.579C>G (p.Tyr193Ter))
  • Residue 94: Binding siteBinding site
  • Residue 96: Binding siteBinding site
  • Residue 119: Binding siteBinding site
  • Residue 198: Binding siteBinding site
  • Residue 199: Binding siteBinding site
  • Residue 208: ClinVar variant [Pathogenic]W208fs (NM_000067.3(CA2):c.621del (p.Trp208fs))

Pocket 2

  • Residue 7: SiteFine-tunes the proton-transfer properties of H-64
  • Residue 7: ClinVar variant [Pathogenic]Y7* (NM_000067.3(CA2):c.21C>A (p.Tyr7Ter))
  • Residue 64: Active siteProton donor/acceptor
  • Residue 236: ClinVar variant [Pathogenic]P236H (NM_000067.3(CA2):c.707C>A (p.Pro236His))

Pocket 3

  • Residue 18: ClinVar variant [Pathogenic]K18E (NM_000067.3(CA2):c.52A>G (p.Lys18Glu))

// Limitations & data provenance

Auto-populated from each section’s own status — not hand-maintained.

Family classificationreturned data
Known ligand precedentreturned data
Interaction fingerprintsreturned data
Functional contextreturned data
Conservationreturned data
Structural analysisreturned data
Similar known proteinsreturned data