PMID- 12102623
OWN - NLM
STAT- MEDLINE
DCOM- 20020826
LR  - 20061115
IS  - 0006-2960 (Print)
IS  - 0006-2960 (Linking)
VI  - 41
IP  - 28
DP  - 2002 Jul 16
TI  - A covalent modification of NADP+ revealed by the atomic resolution structure of
      FprA, a Mycobacterium tuberculosis oxidoreductase.
PG  - 8807-18
AB  - FprA is a mycobacterial oxidoreductase that catalyzes the transfer of reducing
      equivalents from NADPH to a protein acceptor. We determined the atomic resolution
      structure of FprA in the oxidized (1.05 A resolution) and NADPH-reduced (1.25 A
      resolution) forms. The comparison of these FprA structures with that of bovine
      adrenodoxin reductase showed no significant overall differences. Hence, these
      enzymes, which belong to the structural family of the disulfide oxidoreductases, 
      are structurally conserved in very distant organisms such as mycobacteria and
      mammals. Despite the conservation of the overall fold, the details of the active 
      site of FprA show some peculiar features. In the oxidized enzyme complex, the
      bound NADP+ exhibits a covalent modification, which has been identified as an
      oxygen atom linked through a carbonylic bond to the reactive C4 atom of the
      nicotinamide ring. Mass spectrometry has confirmed this assignment. This NADP+
      derivative is likely to form by oxidation of the NADP+ adduct resulting from
      nucleophilic attack by an active-site water molecule. A Glu-His pair is well
      positioned to activate the attacking water through a mechanism analogous to that 
      of the catalytic triad in serine proteases. The NADP+ nicotinamide ring exhibits 
      the unusual cis conformation, which may favor derivative formation. The
      physiological significance of this reaction is presently unknown. However, it
      could assist with drug-design studies in that the modified NADP+ could serve as a
      lead compound for the development of specific inhibitors.
FAU - Bossi, Roberto T
AU  - Bossi RT
AD  - Dipartimento di Genetica e Microbiologia, Universita di Pavia, via Abbiategrasso 
      207, 27100 Pavia, Italy.
FAU - Aliverti, Alessandro
AU  - Aliverti A
FAU - Raimondi, Debora
AU  - Raimondi D
FAU - Fischer, Federico
AU  - Fischer F
FAU - Zanetti, Giuliana
AU  - Zanetti G
FAU - Ferrari, Davide
AU  - Ferrari D
FAU - Tahallah, Nora
AU  - Tahallah N
FAU - Maier, Claudia S
AU  - Maier CS
FAU - Heck, Albert J R
AU  - Heck AJ
FAU - Rizzi, Menico
AU  - Rizzi M
FAU - Mattevi, Andrea
AU  - Mattevi A
LA  - eng
SI  - PDB/1LQT
SI  - PDB/1LQU
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Biochemistry
JT  - Biochemistry
JID - 0370623
RN  - 53-59-8 (NADP)
RN  - EC 1.18.1.- (FprA protein, M tuberculosis)
RN  - EC 1.6.- (NADH, NADPH Oxidoreductases)
SB  - IM
MH  - Amino Acid Sequence
MH  - Crystallography, X-Ray
MH  - Dimerization
MH  - Hydrogen Bonding
MH  - Models, Molecular
MH  - Molecular Sequence Data
MH  - Mycobacterium tuberculosis/*enzymology
MH  - NADH, NADPH Oxidoreductases/*chemistry/metabolism
MH  - NADP/chemistry/*metabolism
MH  - Protein Structure, Secondary
EDAT- 2002/07/10 10:00
MHDA- 2002/08/27 10:01
CRDT- 2002/07/10 10:00
PHST- 2002/07/10 10:00 [pubmed]
PHST- 2002/08/27 10:01 [medline]
PHST- 2002/07/10 10:00 [entrez]
AID - bi025858a [pii]
PST - ppublish
SO  - Biochemistry. 2002 Jul 16;41(28):8807-18.