title: Study on the intermediate ions formed by glutathione peroxidase mimic 2,2'-ditellurobis(2-deoxy-β-cyclodextrin) by electrospray ionization mass spectrometry.
abstract: BACKGROUND
  2,2'-Ditellurobis(2-deoxy-β-cyclodextrin) (2-TeCD) is one of the most well-known glutathione peroxidase (GPx) mimics. However, because the critical reaction intermediates had not previously been isolated or directly detected due to its short lifetime, the catalytic mechanism of 2-TeCD is not very clear and further experiments are needed to characterize each of the intermediates in the catalytic cycle.
  
  
  METHODS
  Using electrospray ionization mass (and tandem) spectrometry (ESI-MS and ESI-MS/MS) experiments, the decomposition of hydrogen peroxide at the expense of glutathione (GSH) catalyzed by 2-TeCD was monitored on-line.
  
  
  RESULTS
  The key intermediates were successfully intercepted and structurally characterized for the first time by coupling a microreactor on-line to the ESI ion source, which permitted the fast screening of intermediates directly from solution.
  
  
  CONCLUSIONS
  The catalytic mechanism of 2-TeCD catalysis has been elaborated based on mass spectrometric data and exerted its peroxidase activity via tellurol, tellurenic acid, and tellurosulfide, in analogy with natural GPX.
authors.affiliation: The State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China.
authors.forename: Aiquan
authors.initials: A
authors.lastname: Jiao
authors.forename: Na
authors.initials: N
authors.lastname: Yang
authors.forename: Xueming
authors.initials: X
authors.lastname: Xu
authors.forename: Zhengyu
authors.initials: Z
authors.lastname: Jin
mesh_terms: D005978:Glutathione / Q000737:chemistry* / Q000378:metabolism*; D005979:Glutathione Peroxidase / Q000737:chemistry / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000737:chemistry* / Q000378:metabolism*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods; D047392:beta-Cyclodextrins / Q000737:chemistry / Q000378:metabolism*
chemical_list: D047392:beta-Cyclodextrins; D006861:Hydrogen Peroxide; D005979:Glutathione Peroxidase; D005978:Glutathione