This led me to search around the Web for info about creatine, and I chanced upon the Journal of Biological Chemistry online edition. Having been a practising chemist (and high school chemistry teacher) for a while during the 1960s, before I diverted to the computer industry, I scanned a few of the abstracts just out of curiosity. For example, there's this one:
Papers In Press, published online ahead of print April 11, 2006
J. Biol. Chem, 10.1074/jbc.M601555200
Submitted on February 17, 2006
Revised on March 30, 2006
Accepted on April 11, 2006
Crystal structure of mammalian cysteine dioxygenase: A novel mononuclear iron center for cysteine thiol oxidation
Chad R. Simmons, Qun Liu, Qingqiu Huang, Quan Hao, Tadhg P. Begley, P. Andrew Karplus, and Martha H. Stipanuk -- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853
Cysteine dioxygenase is a mononuclear iron-dependent enzyme responsible for the oxidation of cysteine with molecular oxygen to form cysteinesulfinate. This reaction commits cysteine to either catabolism to sulfate and pyruvate or to the taurine biosynthetic pathway. Cysteine dioxygenase is a member of the cupin superfamily of proteins. The crystal structure of recombinant rat cysteine dioxygenase has been determined to 1.5 Å resolution, and these results confirm the canonical cupin ß-sandwich fold and the rare cysteinyl-tyrosine intramolecular crosslink (between Cys93 and Tyr157) seen in the recently reported murine cysteine dioxygenase structure. In contrast to the catalytically inactive mononuclear Ni(II) metallocenter present in the murine structure, crystallization of a catalytically competent preparation of rat cysteine dioxygenase revealed a novel tetrahedrally coordinated mononuclear iron center involving three histidines (His86, His88, and His140) and a water molecule. Attempts to acquire a structure with bound ligand using either co-crystallization or soaks with cysteine revealed the formation of a mixed disulfide involving Cys164 near the active site, which may explain previously observed substrate inhibition. This work provides a framework for understanding the molecular mechanisms involved in thiol dioxygenation and sets the stage for exploring the chemistry of both the novel mononuclear iron center and the catalytic role of the cysteinyl-tyrosine linkage.
Wow! And I've been complaining about all of the technical terms and acronyms used in the IT industry (such as the rash of them that have arisen for Web Services and Service Oriented Architecture).
It made me ponder what would happen to us after a cataclysmic global event, such as a huge asteroid colliding with the Earth, or an all-out nuclear war: you know, the aftermath that is a favorite theme of "disaster movies" when civilization fails. It's such a "tangled web of expertise" that we have woven -- and the sum total of our knowledge expands inexorably and exponentially.
What would happen to our hard-won knowledge and skills (such as those in biological chemistry evidenced in the above abstract) after the cataclysm? Oh, it's all too disturbing to contemplate, so I'm going to give up on this train of thought and and go do something nice and mind-numbingly easy like watching the football. Do you blame me?
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