Matches in SemOpenAlex for { <https://semopenalex.org/work/W2006070046> ?p ?o ?g. }
- W2006070046 abstract "Presteady and steady-state kinetic results on the interactions of a wild-type, and the mutant glucoamylases Trp52-->Phe and Trp317-->Phe, from Aspergillus niger with maltose, maltotriose and maltotetraose have been obtained and analyzed. The results are compared with previous ones on the mutants, Trp120-->Phe and Glu180-->Gln, and with results obtained from structure energy minimization calculations based on known three-dimensional structural data. All results are in accordance with a three-step reaction model involving two steps in the substrate binding and a rate-determining catalytic step. Trp317 and Glu180 belong to different subsites, but are placed on the same flank of the active site (beta-flank). The Trp317-->Phe and the Glu180-->Gln mutants show almost identical kinetic results: weakening of the substrate binding, mainly caused by changes in the second reaction step, and practically no change of the catalytic rate. Structure energy minimization calculations show that the same loss of Arg305 and Glu180 hydrogen bonds to the substrate occurs in the Michaelis complexes of each of these mutants. These results indicate that important interactions of the active site may be better understood from a consideration of its flanks rather than of its subsites. The results further indicate differences in the substrate binding mode of maltose and of longer substrates. Trp52 and Trp120 each interact with the catalytic acid, Glu179, and are placed on the flank (alpha-flank) of the active site opposite to Trp317, Arg305 and Glu180. Also the Trp52-->Phe and Trp120-->Phe mutants show kinetic results similar to each other. The catalytic rates are strongly reduced and the substrates are bound more strongly, mainly as a result of the formation of a more stable complex in the second reaction step. All together, the substrate binding mechanism seems to involve an initial enzyme-substrate complex, in which the beta-flank plays a minor role, except for maltose binding; this is followed by a conformational change, in which hydrogen bonds to Arg305 and Glu180 of the beta-flank are established and the correct alignment on the alpha-flank of Glu179, the general acid catalyst, governed by its flexible interactions with Trp52 and Trp120, occurs." @default.
- W2006070046 created "2016-06-24" @default.
- W2006070046 creator A5046731425 @default.
- W2006070046 creator A5055142897 @default.
- W2006070046 creator A5067440189 @default.
- W2006070046 creator A5089839391 @default.
- W2006070046 date "1997-12-01" @default.
- W2006070046 modified "2023-10-17" @default.
- W2006070046 title "Some Details of the Reaction Mechanism of Glucoamylase from Aspergillus Niger- Kinetic and Structural Studies on Trp52Phe and Trp317Phe Mutants" @default.
- W2006070046 cites W1460842808 @default.
- W2006070046 cites W148540243 @default.
- W2006070046 cites W1546595715 @default.
- W2006070046 cites W1683159282 @default.
- W2006070046 cites W1908773263 @default.
- W2006070046 cites W1964562109 @default.
- W2006070046 cites W1966632036 @default.
- W2006070046 cites W1968002171 @default.
- W2006070046 cites W1982534537 @default.
- W2006070046 cites W1988786754 @default.
- W2006070046 cites W1989377542 @default.
- W2006070046 cites W1990087334 @default.
- W2006070046 cites W2001582608 @default.
- W2006070046 cites W2004181587 @default.
- W2006070046 cites W2006965524 @default.
- W2006070046 cites W2007231835 @default.
- W2006070046 cites W2007348762 @default.
- W2006070046 cites W2009976518 @default.
- W2006070046 cites W2014041587 @default.
- W2006070046 cites W2018251713 @default.
- W2006070046 cites W2018420777 @default.
- W2006070046 cites W2019539753 @default.
- W2006070046 cites W2023351934 @default.
- W2006070046 cites W2027560826 @default.
- W2006070046 cites W2027986708 @default.
- W2006070046 cites W2030685318 @default.
- W2006070046 cites W2032649979 @default.
- W2006070046 cites W2033100088 @default.
- W2006070046 cites W2033883812 @default.
- W2006070046 cites W2034964395 @default.
- W2006070046 cites W2037775811 @default.
- W2006070046 cites W2046242540 @default.
- W2006070046 cites W2047325454 @default.
- W2006070046 cites W2054700181 @default.
- W2006070046 cites W2061215285 @default.
- W2006070046 cites W2080653566 @default.
- W2006070046 cites W2081036420 @default.
- W2006070046 cites W2087035585 @default.
- W2006070046 cites W2096057606 @default.
- W2006070046 cites W2106121486 @default.
- W2006070046 cites W2121449154 @default.
- W2006070046 cites W2129875490 @default.
- W2006070046 cites W2154116140 @default.
- W2006070046 cites W2950469006 @default.
- W2006070046 cites W350226238 @default.
- W2006070046 doi "https://doi.org/10.1111/j.1432-1033.1997.00638.x" @default.
- W2006070046 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/9461285" @default.
- W2006070046 hasPublicationYear "1997" @default.
- W2006070046 type Work @default.
- W2006070046 sameAs 2006070046 @default.
- W2006070046 citedByCount "21" @default.
- W2006070046 countsByYear W20060700462013 @default.
- W2006070046 countsByYear W20060700462017 @default.
- W2006070046 crossrefType "journal-article" @default.
- W2006070046 hasAuthorship W2006070046A5046731425 @default.
- W2006070046 hasAuthorship W2006070046A5055142897 @default.
- W2006070046 hasAuthorship W2006070046A5067440189 @default.
- W2006070046 hasAuthorship W2006070046A5089839391 @default.
- W2006070046 hasBestOaLocation W20060700461 @default.
- W2006070046 hasConcept C104317684 @default.
- W2006070046 hasConcept C112887158 @default.
- W2006070046 hasConcept C143065580 @default.
- W2006070046 hasConcept C161790260 @default.
- W2006070046 hasConcept C178790620 @default.
- W2006070046 hasConcept C181199279 @default.
- W2006070046 hasConcept C185592680 @default.
- W2006070046 hasConcept C18903297 @default.
- W2006070046 hasConcept C2775960407 @default.
- W2006070046 hasConcept C2777289219 @default.
- W2006070046 hasConcept C2778197599 @default.
- W2006070046 hasConcept C32909587 @default.
- W2006070046 hasConcept C41183919 @default.
- W2006070046 hasConcept C55493867 @default.
- W2006070046 hasConcept C71240020 @default.
- W2006070046 hasConcept C86803240 @default.
- W2006070046 hasConceptScore W2006070046C104317684 @default.
- W2006070046 hasConceptScore W2006070046C112887158 @default.
- W2006070046 hasConceptScore W2006070046C143065580 @default.
- W2006070046 hasConceptScore W2006070046C161790260 @default.
- W2006070046 hasConceptScore W2006070046C178790620 @default.
- W2006070046 hasConceptScore W2006070046C181199279 @default.
- W2006070046 hasConceptScore W2006070046C185592680 @default.
- W2006070046 hasConceptScore W2006070046C18903297 @default.
- W2006070046 hasConceptScore W2006070046C2775960407 @default.
- W2006070046 hasConceptScore W2006070046C2777289219 @default.
- W2006070046 hasConceptScore W2006070046C2778197599 @default.
- W2006070046 hasConceptScore W2006070046C32909587 @default.
- W2006070046 hasConceptScore W2006070046C41183919 @default.
- W2006070046 hasConceptScore W2006070046C55493867 @default.
- W2006070046 hasConceptScore W2006070046C71240020 @default.
- W2006070046 hasConceptScore W2006070046C86803240 @default.