Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q9UIJ5 (Rec)
 58,342 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An ultrastructural, enzymohistochemical, and immunohistochemical study of the ductus epididymis in normal men was undertaken to investigate the characteristics of the apical mitochondria-rich cells (AMRCs). These cells, which differ morphologically from the principal cells (PCs), appear in isolation in the caput epididymidis (5.8 +/- 1.7 cells per cross-sectional duct) and only occasionally in the corpus epididymidis. The morphologic appearance of AMRCs varies from slender cells extending from the basement membrane to the lumen to apical cells without apparent contact with the basement membrane. The former display a round pale nucleus located in the middle of the epithelium; the apical cells have a dark nucleus, which, surrounded by a narrow cytoplasmic band, protrudes into the lumen. The cytoplasm of AMRCs is electron-dense and contains numerous mitochondria surrounded by rough endoplasmic reticulum cisternae. In the apical portion, there are lysosomes, vesicles with an electron-dense granule, and vacuoles showing a variable size and content. The stereocilia are shorter and less numerous than those of the PCs. The AMRCs are similar to the PCs in the intensely positive reaction for the enzymatic activity acid phosphatase, as well as in the lack of reaction for alkaline phosphatase and phosphorylase activities. AMRCs differ from PCs in: (1) a more intense reaction to the enzymatic activities ATPase, NADP, and succinic dehydrogenease, (2) a more intense immunostaining by AE1/AE3 and Ks4.62 anti-cytokeratin antibodies, and anti-estradiol receptor protein (D5) antibodies, and (3) a lower staining affinity for epithelial membrane antigen (EMA) antibodies. No positive immunostaining for the anti-cytokeratin Ks8.6 antibodies was observed in either AMRCs or PCs.
Anat Rec 1991 Sep
PMID:Apical mitochondria-rich cells in the human epididymis: an ultrastructural, enzymohistochemical, and immunohistochemical study. 172 7

Apomorphine, N-nor-N-propyl-apomorphine, dopamine, L-DOPA, 6-hydroxydopamine and adrenaline were evaluated for genotoxicity using the Ames test and DNA repair-deficient and DNA repair-proficient Bacillus subtilis strains (rec assay, H17/M45; HLL3g/HJ-15). In the absence of an S9 liver homogenate, apomorphine induced frame-shift mutations in Salmonella typhimurium, mainly in strain TA1537; no indication of DNA-damaging effects in B. subtilis was observed. N-Nor-N-propyl-apomorphine was tested using strain TA1537 only and found to be mutagenic. Dopamine, L-DOPA, 6-hydroxydopamine and adrenaline were non-mutagenic when tested without S9, whereas they were all more toxic for DNA repair-deficient than for DNA repair-proficient B. subtilis strains, indicating a DNA-damaging potential. In a second set of experiments the mode of action of apomorphine and the relevance of the positive Ames test data were investigated. Glutathione in physiological concentrations reduced the mutagenic effect of apomorphine in a dose-dependent way, both in the presence and the absence of S9. S9 also reduced the mutagenicity of apomorphine. By comparing the effects of a complete S9 mix with those of a preparation without glucose-6-phosphate and NADP, it became clear that S9 also had an activating effect, overshadowed under standard conditions by its deactivating activity. Apomorphine was not mutagenic under anaerobic conditions. Superoxide dismutase and catalase reduced the mutagenic effect of apomorphine. All test conditions which reduced the mutagenic effect also inhibited the dark discoloration of the tester plates, indicating a retardation of apomorphine oxidation. It can, therefore, be concluded that oxidation of apomorphine leads to mutagenic products which induce frame-shift mutations in Salmonella typhimurium. This oxidation was prevented both by glutathione in concentrations well below physiological levels and/or by catalase and superoxide dismutase. Under these conditions, apomorphine was non-mutagenic in therapeutic concentrations as well as at higher dose levels. The possibility of genotoxic side effects occurring in patients treated with apomorphine as an emetic drug is therefore considered to be very unlikely.
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PMID:Genotoxicity of apomorphine and various catecholamines in the Salmonella mutagenicity test (Ames test) and in tests for primary DNA damage using DNA repair-deficient B. subtilis strains (rec assay). 643 Dec 80

Until recently, it was generally believed that enzymatic oxidation and reduction requires the participation of either a nicotinamide (NAD(P)+) or a flavin (FAD, FMN), in agreement with the existence of NAD(P)/H-dependent dehydrogenases/reductases and flavoprotein dehydrogenases/reductases/oxidases. However, during the past 20 years, the unraveling of the enzymology of the oxidation and reduction of C1-compounds by bacteria has led to the discovery of many new redox cofactors, some of them discussed here as they have a wider physiological significance than just enabling enzymatic C1-conversions to occur. A good example is the quinone cofactors, encompassing PQQ (2,7,9-tricarboxy-1H-pyrrolo[2,3-f]-quinoline-4,5-dione), TTQ (tryptophyl tryptophanquinone), TPQ (topaquinone), LTQ (lysyl topaquinone), and several others whose structures have still to be elucidated. Another example is mycothiol (1-O-(2'-[N-acetyl-L-cysteinyl]amido-2'-deoxy-alpha-D-glucopyranosyl)-D-myo-inosoitol), the counterpart of glutathione, once thought to be a universal coenzyme. Because these novel cofactors assist in reactions that can also be catalyzed by already known enzyme "classic cofactor" combinations, and first indications suggest that the chemistry of the reactions is not unique, one may wonder about the evolutionary background for this cofactor diversity. However, as will be illustrated by examples, from a practical point of view the diversity is beneficial, as it has increased the arsenal of enzymes suitable for application.
Chem Rec 2001
PMID:Cofactor diversity in biological oxidations: implications and applications. 1189 60