Abstract

A knowledge of protein structure requires a determination of which cysteine is connected to which cysteine. We cyanylate and cleave the peptide bond at the N-terminus of free cysteine residues. From the known sequence, we can anticipate the mass of degraded peptides for a given disulfide bond connectivity. We presently use cyanodiaminopyridium (CDAP) tetrafluoroborate, which cyanylates the protein at pH 3 to avoid disulfide bond exchange. We have established conditions for partial reduction at low pH which also avoids disulfide bond exchange. We have used this approach with ribonuclease A, which gives four singly reduced isomers, each having a different disulfide bond reduced. These isoforms were cyanylated and cleaved for analysis by MALDI-MS allowing us to verify the pairing of the disulfide bonds. We are also exploring the applicability of alternate cyanylating reagents to provide us with some flexibility in the chemical approach to solving a structural problem. We have synthesized a new reagent, 2-thiocyanopyridine, which will be characterized for its potency in cyanylating model compounds such as ?-lactoglobulin and others.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Biotechnology Resource Grants (P41)
Project #
3P41RR000480-28S1
Application #
6258782
Study Section
Project Start
1997-06-01
Project End
1999-11-30
Budget Start
1998-10-01
Budget End
1999-09-30
Support Year
28
Fiscal Year
1999
Total Cost
Indirect Cost

  Institution

Name
Michigan State University
Department
Type
DUNS #
193247145
City
East Lansing
State
MI
Country
United States
Zip Code
48824

  Publications

Peri, S P; Bhadti, V S; Somerville-Armstrong, K S et al. (1999) Affinity reagents for cross-linking hemoglobin: bis(phenoxycarbonylethyl)phosphinic acid (BPCEP) and bis(3-nitrophenoxycarbonylethyl)phosphinic acid (BNCEP). Hemoglobin 23:1-20
Chen, H M; Sood, R; Hosmane, R S (1999) An efficient, short synthesis and potent anti-hepatitis B viral activity of a novel ring-expanded purine nucleoside analogue containing a 5:7-fused, planar, aromatic, imidazo[4,5-e][1,3]diazepine ring system. Nucleosides Nucleotides 18:331-5
Bretner, M; Beckett, T D; Sood, R K et al. (1999) Substrate/inhibition studies of bacteriophage T7 RNA polymerase with the 5'-triphosphate derivative of a ring-expanded ('fat') nucleoside possessing potent antiviral and anticancer activities. Bioorg Med Chem 7:2931-6
Agasimundin, Y S; Mumper, M W; Hosmane, R S (1998) Inhibitors of glycogen phosphorylase b: synthesis, biochemical screening, and molecular modeling studies of novel analogues of hydantocidin. Bioorg Med Chem 6:911-23
Hosmane, R S; Peri, S P; Bhadti, V S et al. (1998) Bis[2-(4-carboxyphenoxy)carbonylethyl]phosphinic acid (BCCEP): a novel affinity reagent for the beta-cleft modification of human hemoglobin. Bioorg Med Chem 6:767-83
Rajappan, V P; Hosmane, R S (1998) Analogues of azepinomycin as inhibitors of guanase. Nucleosides Nucleotides 17:1141-51
Hosmane, R S; Hong, M (1997) How important is the N-3 sugar moiety in the tight-binding interaction of coformycin with adenosine deaminase? Biochem Biophys Res Commun 236:88-93
Lopez-Lara, I M; Orgambide, G; Dazzo, F B et al. (1993) Characterization and symbiotic importance of acidic extracellular polysaccharides of Rhizobium sp. strain GRH2 isolated from acacia nodules. J Bacteriol 175:2826-32
Watson, J T; Kayganich, K (1989) Novel sample preparation for analysis by electron capture negative ionization mass spectrometry. Biochem Soc Trans 17:254-7
Kassel, D B; Kayganich, K A; Watson, J T et al. (1988) Utility of ion source pretreatment with chlorine-containing compounds for enhanced performance in gas chromatography/negative ionization mass spectrometry. Anal Chem 60:911-7

Showing the most recent 10 out of 11 publications