Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.8.1.4 (diaphorase)
 2,754 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

By means of starch electrophoresis, 52 proteins and enzymes of Microtus arvalis and M. subarvalis were studied to establish the extent of their similarity. Out of 52 markers studied, 7 proteins and enzymes had different electrophoretic mobility: glucose-6-phosphate dehydrogenase (G6PD), phosphogluconate dehydrogenase (PGD), diaphorase (DP), adenylate kinase (AK), lactate dehydrogenase B (LDHB), alpha-galactosidase (GAL) and hemoglobin (Hb), which make up to 13% of all the enzymes and proteins studied. The differences found between the two species studied by electrophoretic mobility of G6PD, AK, GAL and Hb, as well as the absence of intraspecific polymorphism for the above proteins permit to consider these proteins as species-specific markers, with the help of which M. arvalis and M. subarvalis can be distinguished. It should be emphasized that intraspecific polymorphism was found for PGD, LDHB and DP in M. arvalis, while in M. subarvalis these proteins were monomorphic and identical, in their electrophoretic mobility, to one of electrophoretic variants of M. arvalis. Therefore, only one of allelic variants of PGD, LDHB and DP is species-specific. Estimation of the extent of genetic similarity based on analysis of distribution of gene frequencies for polymorphic loci of M. arvalis and M. subarvalis by means of Nei's method gave the value of 0.312, the genetic distance being 1.164. The data obtained, together with the known cytogenetic data, point to a species rank of the species studied. Moreover, in spite of the morphological similarity between M. arvalis and M. subarvalis, the estimation of genetic similarity proved to be close to that for morphologically contrasting species.
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PMID:[Evaluation of the degree of genetic divergence in the twin species of the common vole Microtus arvalis and Microtus subarvalis (Rodentia)]. 638 3

The electrophoretic mobilities of 52 enzymes and proteins were used as measures of the genetic similarity between the sibling species Microtus arvalis and M. subarvalis. The two vole species differed in the electrophoretic mobilities of seven (glucose-6-phosphate dehydrogenase, adenylate kinase, diaphorase, lactate dehydrogenase-A, alpha-galactosidase, 6-phosphogluconate dehydrogenase, and hemoglobin) of these markers. This allowed us to accept the seven markers assayed as species-specific markers. Based on the frequency distribution of the genes at the polymorphic loci of M. arvalis and M. subarvalis, the degree of their genetic similarity was estimated as 0.312 and the genetic distance as 1.164 by Nei's formula. The estimates for genetic similarity were close to those obtained for species recognized as distinct.
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PMID:An estimation of the degree of the genetic divergence of sibling species Microtus arvalis and Microtus subarvalis (Rodentia) based on electrophoretic analysis. 639 94

In the present study, we have characterized the dihydrolipoamide dehydrogenase (DLDH) of Strepto-coccus pneumoniae and its role during pneumococcal infection. We have also demonstrated that a lack of DLDH results in a deficiency in alpha-galactoside metabolism and galactose transport. DLDH is an enzyme that is classically involved in the three-step conversion of 2-oxo acids to their respective acyl-CoA derivatives, but DLDH has also been shown to have other functions. The dldh gene was virtually identical in three pneumococcal strains examined. Besides the functional domains and motifs associated with this enzyme, analysis of the pneumococcal dldh gene sequence revealed the presence of an N-terminal lipoyl domain. DLDH-negative bacteria totally lacked DLDH activity, indicating that this gene encodes the only DLDH in S. pneumoniae. These DLDH-negative bacteria grew normally in vitro but were avirulent in sepsis and lung infection models in mice, indicating that DLDH activity is necessary for the survival of pneumococci within the host. The lack of virulence was not associated with a loss of 2-oxo acid dehydrogenase activity, as the wild-type pneumococcal strains did not contain activity of any of the known 2-oxo acid enzyme complexes. Instead, studies of carbohydrate utilization demonstrated that the DLDH-negative bacteria were impaired for alpha-galactoside and galactose metabolism. The DLDH mutants lost their ability to oxidize or grow with galactose or melibiose as sole carbon source and showed reduced oxidation and growth on raffinose or stachyose. The bacteria had an 85% reduction in alpha-galactosidase activity and showed virtually no transport of galactose into the cells, which can explain these phenotypic changes. The DLDH-negative bacteria produced only 50% of normal capsular polysaccharide, a phenotype that may be associated with impaired carbohydrate metabolism.
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PMID:Characterization of the dihydrolipoamide dehydrogenase from Streptococcus pneumoniae and its role in pneumococcal infection. 1197 81

Streptococcus pneumoniae strains lacking the enzyme dihydrolipoamide dehydrogenase (DLDH) show markedly reduced ability to grow on raffinose and stachyose as sole carbon sources. Import of these sugars occurs through the previously characterized raffinose ATP-binding cassette (ABC) transport system, encoded by the raf operon, that lacks the necessary ATP-binding protein. In this study, we identified the raffinose ATP-binding protein RafK and showed that it was directly involved in raffinose and stachyose import. RafK carries a C-terminal regulatory domain present in a subset of ATP-binding proteins that has been involved in both direct regulation of transporter activity (inducer exclusion) and transcription of transporter genes. Pneumococci lacking RafK showed a 50- to 80-fold reduction in expression of the raf operon genes aga (alpha-galactosidase) and rafEFG (raffinose substrate binding and permease genes), and both glucose and sucrose inhibited raffinose uptake through inducer exclusion. Like RafK, the presence of DLDH also activated the expression of raf operon genes, as DLDH-negative pneumococci showed a significantly decreased expression of aga and rafEFG, but DLDH did not regulate rafK or the putative regulatory genes rafR and rafS. DLDH also bound directly to RafK both in vitro and in vivo, indicating the possibility that DLDH regulates raffinose transport by a direct interaction with the regulatory domain of the transporter. Finally, although not as attenuated as DLDH-negative bacteria, pneumococci lacking RafK were significantly outcompeted by wild-type bacteria in colonization experiments of murine lung and nasopharynx, indicating a role for raffinose and stachyose transport in vivo.
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PMID:Role of dihydrolipoamide dehydrogenase in regulation of raffinose transport in Streptococcus pneumoniae. 2160 35