PMID- 16337878
OWN - NLM
STAT- MEDLINE
DCOM- 20060316
LR  - 20131121
IS  - 0891-5849 (Print)
IS  - 0891-5849 (Linking)
VI  - 40
IP  - 1
DP  - 2006 Jan 1
TI  - Taurine chloramine is more selective than hypochlorous acid at targeting critical 
      cysteines and inactivating creatine kinase and glyceraldehyde-3-phosphate 
      dehydrogenase.
PG  - 45-53
AB  - Hypochlorous acid (HOCl) and chloramines are produced by the neutrophil enzyme, 
      myeloperoxidase. Both react readily with thiols, although chloramines differ from 
      HOCl in discriminating between low molecular weight thiols on the basis of their 
      pKa. Here, we have compared the reactivity of HOCl and taurine chloramine with 
      thiol proteins by examining inactivation of creatine kinase (CK) and 
      glyceraldehyde-3-phosphate dehydrogenase (GAPDH). With both enzymes, loss of 
      activity paralleled thiol loss. For CK both were complete at a 1:1 taurine 
      chloramine:thiol mole ratio. For GAPDH each chloramine oxidized two thiols. Three 
      times more HOCl than taurine chloramine was required for inactivation, indicating 
      that HOCl is less thiol specific. Competition studies showed that thiols of CK 
      were 4 times more reactive with taurine chloramine than thiols of GAPDH (rate 
      constants of 1200 and 300 M-1s-1 respectively). These compare with 205 M-1s-1 for 
      cysteine and are consistent with their lower pKa's. Both enzymes were equally 
      susceptible to HOCl. GSH competed directly with the enzyme thiols for taurine 
      chloramine and protected against oxidative inactivation. At lower GSH 
      concentrations, mixed disulfides were formed. We propose that chloramines should 
      preferentially attack proteins with low pKa thiols and this could be important in 
      regulatory processes.
FAU - Peskin, Alexander V
AU  - Peskin AV
AD  - Free Radical Research Group, Department of Pathology, Christchurch School of 
      Medicine and Health Sciences, P.O. Box 4345, Christchurch, New Zealand. 
      alexander.peskin@chmeds.ac.nz
FAU - Winterbourn, Christine C
AU  - Winterbourn CC
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20050906
PL  - United States
TA  - Free Radic Biol Med
JT  - Free radical biology & medicine
JID - 8709159
RN  - 0 (Disulfides)
RN  - 0 (Enzyme Inhibitors)
RN  - 0 (Oxidants)
RN  - 0 (Sulfhydryl Compounds)
RN  - 1EQV5MLY3D (Taurine)
RN  - 51036-13-6 (N-chlorotaurine)
RN  - 712K4CDC10 (Hypochlorous Acid)
RN  - AE28F7PNPL (Methionine)
RN  - EC 1.2.1.- (Glyceraldehyde-3-Phosphate Dehydrogenases)
RN  - EC 2.7.3.2 (Creatine Kinase)
RN  - GAN16C9B8O (Glutathione)
RN  - K848JZ4886 (Cysteine)
SB  - IM
MH  - Animals
MH  - Binding, Competitive
MH  - Creatine Kinase/*antagonists & inhibitors/metabolism
MH  - Cysteine/*metabolism
MH  - Disulfides/metabolism
MH  - Enzyme Inhibitors/*pharmacology
MH  - Glutathione/metabolism
MH  - Glyceraldehyde-3-Phosphate Dehydrogenases/*antagonists & inhibitors/metabolism
MH  - Hypochlorous Acid/*pharmacology
MH  - Methionine/metabolism
MH  - Muscles/enzymology
MH  - Oxidants/*pharmacology
MH  - Oxidation-Reduction
MH  - Rabbits
MH  - Sulfhydryl Compounds/metabolism
MH  - Taurine/*analogs & derivatives/pharmacology
EDAT- 2005/12/13 09:00
MHDA- 2006/03/17 09:00
CRDT- 2005/12/13 09:00
PHST- 2005/05/12 00:00 [received]
PHST- 2005/07/11 00:00 [revised]
PHST- 2005/08/09 00:00 [accepted]
PHST- 2005/12/13 09:00 [pubmed]
PHST- 2006/03/17 09:00 [medline]
PHST- 2005/12/13 09:00 [entrez]
AID - S0891-5849(05)00457-0 [pii]
AID - 10.1016/j.freeradbiomed.2005.08.019 [doi]
PST - ppublish
SO  - Free Radic Biol Med. 2006 Jan 1;40(1):45-53. doi: 
      10.1016/j.freeradbiomed.2005.08.019. Epub 2005 Sep 6.