This year we have again been involved in many projects relating to the analysis of peptides and proteins brought to our attention by researchers at NHLBI and NIH. Among many others, these include the development of new bridging agents to determine protein structure using mass spectrometry, determination of certain sites overalkylated with iodoacetamide, determination of a phosphorylation site in recombinant PKC, evaluation of a drug-resistant HIV protease-C95F mutation, elucidation of the structure of a putative endogenous aldose reductase inhibitor, identified a fire-blight compound as the known dihomoserine isourea, identified structures of reaction products of KNI-272 a putative anti-HIV drug,determined phosphorylation sites of IRS1 by PKC-zeta, identified several proteins from 1D and 2D gels including DNA-binding protein, GB3 colocalized proteins in colon cancer and proteins coprecipitated with NHE3 in intestinal cancer, determined glutathionylation of actin under oxidative stress, evaluated ICAT methods on BSA and laminin, performed de-novo sequencing of a novel protein in amoeba, determined phosphorylation sites in PAK, PLC-beta-1 and gamma 2.