Differential exchange of the C2 hydrogens of histidine side chains in native proteins: proposed general technique for the assignment of histidine nmr peaks in proteins

Conference · Mon Jan 01 04:00:00 EST 1973

OSTI ID:4399296

Markley, J L; Cheung, S M; Klein, P D; Peterson, S V ^[1]

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1. eds.

From 1st international conference on stable isotopes in chemistry, biology, and medicine; Argonne, Illinois, USA (9 May 1973). In proceedings of the first international conference on stable isotopes in chemistry, biology, and medicine. The rates of deuterium exchange at the C2-H position of individual histidine residues in native proteins were followed by means of /sup 1/H-NMR spectroscopy. Conditions were found for the differential exchange of the histidine residues of bovine ribonuclease A STA4 histidines!, soybean trypsin inhibitor (Kunitz) STA2 histidines!, chicken ovomucoid STA4 histidines!, and staphylococcal nuclease STA3 histidines!. The factors influencing histidine C2-H exchange rates in proteins as well as uses of the differential exchange reaction for studies of protein structure are discussed. A general technique based on differential hydrogen exchange is proposed for assigning histidine NMR peaks of proteins to specific residues in the amino acid sequence. The procedure consists of correlating the rates of deuterium exchange of the histidine NMR peaks with the rates of tritium exchange into individual histidines. Model studies were carried out with the tripeptide glycl-histidylglycine. Tritium exchange into the tripeptide showed a normal primary deuterium isotope effect (k/sub H//k/sub D/ = 7.5) suggesting that the rate limiting step of the exchange reaction is the breakage of the carbon-hydrogen bond. (57 references.) (auth)

• Research Organization: Purdue Univ., West Lafayette, IN; Argonne National Lab., Ill. (USA)
• NSA Number: NSA-29-000144
• OSTI ID: 4399296
• Report Number(s): CONF-730525--
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

*DEUTERIUM-- ISOTOPIC EXCHANGE
*TRITIUM-- ISOTOPIC EXCHANGE
CHEMICAL REACTION KINETICS
HISTIDINE
N40220 --Chemistry--Inorganic
Organic
& Physical Chemistry--Isotopic Effects
N40230* --Chemistry--Inorganic
Organic
& Physical Chemistry--Isotope Exchange & Isotope Separation
NUCLEAR MAGNETIC RESONANCE
PROTEINS
RESIDUES
SPECTROSCOPY
TRITIUM COMPOUNDS