Biochemistry Commons^™

Activation In Vitro Of Transfer Rna-Guanine Ribosyltransferase By Protein Kinase C, Panayota Eriotou

Chemistry & Biochemistry Theses & Dissertations

The purpose of this study was to isolate and purify the enzymes, transfer RNA-guanine ribosyltrasferase and protein kinase C, and to determine whether the phosphorylating enzyme activates the insertion enzyme in vitro. Transfer RNA-guanine ribosyltransferase lost activity within several days after isolation and total, complete reactivation was accomplished in the presence of protein kinase C. This demonstrated that ribosyltransferase's instability is related to the degree of its phosphorylation. It is proposed that modification of tRNA is controlled by protein kinase C. Deactivation of the insertion enzyme leads to hypomodified tRNA which in turn is associated with neoplasia. Potential use …

Determination Of Human Sperm Cell Acrosin Activity From Normal And Subfertile Men, Dilrowshan H. Haque

Chemistry & Biochemistry Theses & Dissertations

Acrosin is an acrosomal enzyme which is reported to be involved in sperm penetration through cumulus, zona, and ooplasma. This enzyme has been reported to be significantly lower in sperm of infertile men compared to sperm of fertile men. The acrosin assay which has been developed can be used for studies in patients with suspected infertility and may be used on a fraction of most semen specimens being evaluated in a clinical andrology laboratory.

Within-run precision studies yielded coefficients of variation of 11% for a low-activity pool and 9% for normalactivity pool specimens. Between-run precision studies using a single donor …

The Synthesis And Biochemical Evaluation Of Potential Acetylcholinesterase Reactivators, Andrea Mcdearmid Lunsford

Chemistry & Biochemistry Theses & Dissertations

Objectives of this research were to (1) synthesize, and (2) evaluate new compounds which would be potential reactivators of organophosphate-inhibited acetylcholinesterase.

A series of 1,8-diazafluorenone and 2,2'bipyridylketone oximes and oxime methiodides were synthesized (11, 13, 14, 22, 24). These compounds were developed as structural analogs of 2-PAM (2-Pyridinealdoxime methiodide) and TMB-4 (1,1Trimethylene-Bis(4-formylpyridinium bromide)dioxime), the current drugs of choice for treatment of organophosphorous poisoning.

Acetylcholinesterase from electric eel was inhibited with DFP (diisopropylfluorophosphate), an irreversible-type inhibitor, and the inhibited enzyme was treated with the various reactivator compounds. The reactivation assays were monitored with pH stat apparatus, and the data were evaluated …

Multiple Forms Of Nicotinamide Adenine Dinucleotide Glycohydrolase From Bull Semen, Stanley D. Yeatts Ii

Chemistry & Biochemistry Theses & Dissertations

Nicotinamide adenine dinucleotide glycohydrolase (NADase) of bull semen is an extracellular, soluble enzyme capable of catalyzing the hydrolysis of the nicotinamide N-ribosidic linkage of NAD⁺. In search for a rapid, simple procedure for the preparation of this enzyme, it was found that Matrex Gel Red A (Amicon) column packing served very well as an affinity gel for NADase. The enzyme was applied to the Matrex Red A column (21 cm x 1.5 cm) in 10 mM sodium phosphate buffer, pH 6.0. Surprisingly, two fractions of NADase activity were obtained when the column was eluted with a sodium chloride …