Open AccessChain Length Effects of n ‐Alkyl 1‐Oxygen‐and n ‐Alkyl 1‐Thio‐β‐ d ‐Xylopyranosides on β‐ d ‐Xylosidases
Author(s) -
KerstersHilderson H.,
Claeyssens M.,
Loontiens F. G.,
Krynski A.,
Bruyne C. K.
Publication year - 1970
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1970.tb00866.x
Subject(s) - alkyl , chemistry , thio , aspergillus niger , bacillus pumilus , hydrolysis , oxygen , stereochemistry , medicinal chemistry , homologous series , organic chemistry , biochemistry , bacteria , biology , genetics
The effect of an homologous series of n ‐alkyl β‐ d ‐xylopyranosides (from methyl to octyl) and n ‐alkyl 1‐thio‐β‐ d ‐xylopyranosides (from methyl to hexyl) on the activity of β‐ d ‐xylosidases from different origins ( Aspergillus niger, Aspergillus oryzae and Bacillus pumilus 12) was investigated. Hydrolysis of n ‐alkyl β‐ d ‐xylopyranosides (oxygen derivatives) was only measurable with the A. niger β‐ d ‐xylosidase, where maximal hydrolysis was observed with the n ‐butyl derivative. Furthermore the behaviour of the series of oxygen and sulfur derivatives was purely competitive with respect to the hydrolysis of p ‐nitrophenyl β‐ d ‐xylopyranoside by all of the three enzymes. The inhibition constants decreased with increasing chain length for both series and both fungal enzymes. For B. pumilus 12 such a relationship was only found for the thiocompounds, whereas for the oxygen series a pronounced maximal inhibition was observed for the n ‐butyl and n ‐pentyl derivatives. The contribution of hydrophobic regions at or near the active site is discussed and speculative interpretations are presented.