Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.4.1.4 (glutamate dehydrogenase)
 4,358 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to provide a basis for obtaining further information concerning the host response to Helicobacter pylori urease, four assay methods for detecting urease-inhibiting activity in serum were examined. A quantitative assay, established in a COBAS BIO centrifugal fast analyzer and based on detection of the consumption of NADH by glutamate dehydrogenase stimulated by ammonia production, was considered most suitable for large-scale serological work. Serum samples from 63 children (aged 5 to 16 years), 28 of whom had seropositive H. pylori gastritis, were assayed. One of the serum samples in this latter group showed significant inhibitory activity. This serum sample was one of 13 in the seropositive group known to bind to urease antigen. It showed no inhibitory activity against Bacillus pasteurii or jack bean urease. Protein A binding and heat treatment indicated that the inhibitory activity was immunoglobulin G mediated. The patient from whom this sample was collected showed no distinctive features in his illness. The COBAS BIO analyzer-based urease inhibition assay provides a new tool for studying one aspect of the host response to H. pylori infection.
 ...
PMID:Assay of urease-inhibiting activity in serum from children infected with Helicobacter pylori. 158 44

The hybridoma, 62H3, which secretes a monoclonal IgG2b with anti-HLA-DR specificity, was expanded in pristane-primed BALB/c mice and the antibody was isolated from the ascitic fluid by affinity chromatography on Protein A-Sepharose. The purified IgG2b antibody was tested by an enzyme immunoassay for antibody activity against a panel of 40 self and non-self antigens. It was found to react strongly with beta-galactosidase, actin, glutamate dehydrogenase, rabbit and human IgG and di- and trinitrophenyl groups; and moderately with tubulin, insulin and phosphorylcholine; but it did not react with various other self and non-self antigens, such as DNA, albumin, keyhole limpet hemocyanin, hen lysozyme and horseradish peroxidase. Fab and Fc fragments were prepared from this IgG2b by papain proteolysis. The Fab fragment possessed the same spectrum of polyreactivities as the native IgG2b, whereas no activity was detected with the Fc fraction. In order to investigate the properties of the antigen binding site, the actin, TNP and rabbit IgG antibody activities were studied in more detail by enzyme immunoassay, Western blot and immunocytochemistry. The monomolecular nature of this multireactivity was confirmed by immunoabsorption analysis. Furthermore, 62H3 monoclonality was also verified by comparative isoelectric focusing and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis with other monospecific antibodies. The dissociation constants (Kd) of antigen-antibody equilibria in solution were measured. The Kd for actin was 1.11 +/- 0.24 x 10(-5) M and the Kd for TNP-BSA was 8.7 +/- 0.51 x 10(-7) M. No interaction with rabbit IgG could be detected in solution. These findings raise the question of the possible implication in autoimmune pathology or in normal physiology of IgG class polyspecific antibodies with solid-phase restricted cross-reactive rheumatoid factor activity.
 ...
PMID:Immunochemical studies of a murine polyreactive IgG2b autoantibody with rheumatoid factor activity. 277 Jul 48

Chlorella sorokiniana cells, cultured for 12 hours in 30 millimolar ammonium medium, contained an ammonium inducible nicotinamide adenine dinucleotide phosphate-specific glutamate dehydrogenase (NADP-GDH) isoenzyme with subunits having a molecular weight of 53,000. In vitro translation of total cellular poly(A)(+) RNA, isolated from fully induced cells, resulted in synthesis of an NADP-GDH antigen with a molecular weight of 58,500. The 58,500 dalton antigen was processed in vitro, with a 100,000g supernatant prepared from broken fully induced Chlorella cells, to a protein with a molecular weight of 53,000. These data support the inference that the NADP-GDH subunit (M(r) = 53,000) is initially synthesized as a larger precursor protein (M(r) = 58,500). By use of a cytochemical staining procedure, dependent upon NADP-GDH catalytic activity, the holoenzyme was shown to be chloroplast-localized. An immunoelectron microscopy procedure, employing anti-NADP-GDH immunoglobulin G and Protein A-gold complex, showed that NADP-GDH antigen was absent from the nucleus but present in both the chloroplast and cytosol. Since synthesis of the enzyme can be inhibited by cycloheximide, the detection of NADP-GDH antigen in the cytosol was probably due to binding of the NADP-GDH antibody to nascent polypeptide chains of the precursor-protein being synthesized on cytosolic 80S ribosomes.
 ...
PMID:Evidence for Chloroplastic Localization of an Ammonium-Inducible Glutamate Dehydrogenase and Synthesis of Its Subunit from a Cytosolic Precursor-Protein in Chlorella sorokiniana. 1666 19