PDBsum entry 5ekm

Lyase/lyase inhibitor

PDB id: 5ekm

Contents

Protein chain

257 a.a.

Ligands

GOL

TG5

Metals

_ZN

_NA

Waters ×231

PDB id:

5ekm

Name:

Lyase/lyase inhibitor

Title:

Human carbonic anhydrase ii complexed with a two-faced guest

Structure:

Carbonic anhydrase 2. Chain: a. Synonym: carbonate dehydratase ii,carbonic anhydrasE C,cac,carbonic anhydrase ii,ca-ii. Engineered: yes. Mutation: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Gene: ca2. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008.

Resolution:

1.33Å R-factor: 0.143 R-free: 0.167

Authors:

B.W.Roose,I.J.Dmochowski

Key ref:

Y.Wang et al. (2016). Programming A Molecular Relay for Ultrasensitive Biodetection through (129)Xe NMR. Angew Chem Int Ed Engl, 55, 1733-1736. PubMed id: 26692420 DOI: 10.1002/anie.201508990

Date:

03-Nov-15 Release date: 06-Jan-16

Protein chain

P00918  (CAH2_HUMAN) -  Carbonic anhydrase 2 from Homo sapiens

Seq: 260 a.a.

Struc: 257 a.a.

Enzyme reactions

• Enzyme class 2: E.C.4.2.1.1 - carbonic anhydrase.
• Reaction: hydrogencarbonate + H⁺ = CO2 + H2O
• Cofactor: Zn(2+)
• Enzyme class 3: E.C.4.2.1.69 - cyanamide hydratase.
• Reaction: urea = cyanamide + H2O

Note, where more than one E.C. class is given (as above), each may correspond to a different protein domain or, in the case of polyprotein precursors, to a different mature protein.

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

reference

DOI no: 10.1002/anie.201508990

Angew Chem Int Ed Engl 55:1733-1736 (2016)

PubMed id: 26692420

Programming A Molecular Relay for Ultrasensitive Biodetection through (129)Xe NMR.

Y.Wang, B.W.Roose, J.P.Philbin, J.L.Doman, I.J.Dmochowski.

ABSTRACT

A supramolecular strategy for detecting specific proteins in complex media by using hyperpolarized (129) Xe NMR is reported. A cucurbit[6]uril (CB[6])-based molecular relay was programmed for three sequential equilibrium conditions by designing a two-faced guest (TFG) that initially binds CB[6] and blocks the CB[6]-Xe interaction. The protein analyte recruits the TFG and frees CB[6] for Xe binding. TFGs containing CB[6]- and carbonic anhydrase II (CAII)-binding domains were synthesized in one or two steps. X-ray crystallography confirmed TFG binding to Zn(2+) in the deep CAII active-site cleft, which precludes simultaneous CB[6] binding. The molecular relay was reprogrammed to detect avidin by using a different TFG. Finally, Xe binding by CB[6] was detected in buffer and in E. coli cultures expressing CAII through ultrasensitive (129) Xe NMR spectroscopy.