Hydroxyl radicals (•OH) cause non-enzymic scission of polysaccharides in diverse biological systems. Such reactions can be detrimental (e.g. causing rheumatic and arthritic diseases in mammals) or beneficial (e.g. promoting the softening of ripening fruit, and biomass saccharification). Here we present a method for documenting •OH action, based on fluorescent labelling of the oxo groups that ar...

Reduction of aldehydes and ketones to the corresponding alcohols in the presence of sodium cyanoborohdride as reductive agent and Tonsil clay as catalyst under solvent free conditions was investigated. Tonsil (catalyst) decreased the reduction time of each aldehyde and ketone to proportional alcohols in comparison with their reduction in the absence of catalyst with high degree purity of alcoho...

DNA-protein cross-links (DPCs) are formed upon exposure to a variety of chemical and physical agents and pose a threat to genomic integrity. In particular, acrolein and related aldehydes produce DPCs, although the chemical linkages for such cross-links have not been identified. Here, we report that oligodeoxynucleotides containing 1,N(2)-deoxyguanosine adducts of acrolein, crotonaldehyde, and t...

The biological importance of lipopolysaccharides (LPS), components of bacterial cell wall has not been explained sufficiently. The glycine present in these structures could play an important role in the immunological response after bacterial infections and during sepsis. In our studies we obtained synthetic and stable substituted glycinated 1-thioglycosides derivatives of monosaccharides, e.g.,...

We have reductively alkylated deoxynojirimycin imino sugars using sodium cyanoborohydride to provide an efficient means of generating a series of N-alkylated compounds containing 4-18 carbon side chains. The yields were greater than 90% using a variety of aldehydes of different chain lengths, and after purification were >95% pure using (1)H-NMR. Radiolabelled compounds were prepared using sodiu...

The reaction of glyceraldehyde (aldotriose) with hemoglobin A is analogous to the nonenzymic glycosylation of the protein with glucose in that the initial reversible Schiff base adduct (aldimine) of aldotriose undergoes Amadori rearrangement as does that of aldohexose to form the more stable ketoamine adduct. The modification of the alpha-amino group on Val-1(beta) of hemoglobin A as a ketoamin...

1,2-Diamine derivatives are valuable building blocks to heterocyclic compounds and important precursors of biologically relevant compounds. In this respect, amino acid-derived β-keto esters are a suitable starting point for the synthesis of β,γ-diamino ester derivatives through a two-step reductive amination procedure with either simple amines or α-amino esters. AcOH and NaBH(3)CN are the addit...

Multiple lines of evidence are presented which support the conclusion that 2-keto-4-hydroxyglutarate aldolase, obtained in homogeneous form (over 2,000-fold purified) from extracts of Escherichia coli K-12, is a trimeric oligomer composed of identical or nearly identical subunits. The data include: (a) determining an overall average molecular weight of 64,700 for the native enzyme using the met...

A chemically selective procedure for covalent modification of Schiff base-forming binding sites in proteins is demonstrated in vitro. In vivo studies show that the same procedure produces a selective anosmia ("odor blindness") when applied to the olfactory epithelia of experimental animals. Surgical experiments confirm that the sense of smell is specifically affected. The hypothesis that olfact...

New site-specific protein labeling (SSPL) reactions for targeting-specific, short peptides could be useful for the real-time detection of proteins inside of living cells. One SSPL approach matches bioorthogonal reagents with complementary peptides. Here, hydrazide reactive peptides were selected from phage-displayed libraries using reaction-based selections. Selection conditions included washes...