β-Fructofuranosidase and sucrose phosphorylase of rumen bacterium Pseudobutyrivibrio ruminis strain 3.
The subject of this study was the fructan and sucrose degrading enzymes of bacterium Pseudobutyrivibrio ruminis strain 3. It was stated that cell extract from bacteria growing on inulin contained β-fructofuranosidase (EC 3.2.1.80 and/or EC 3.2.1.26) and sucrose phosphorylase (EC 2.4.1.7), while the bacteria maintained on sucrose showed only phosphorylase. Partially purified β-fructofuranosidase digested inulooligosaccharides and sucrose to fructose or fructose and glucose, respectively, but was unable to degrade the long chain polymers of commercial inulin and Timothy grass fructan. Digestion rate of inulooligosaccharides fit Michaelis-Menten kinetics with V(max) 5.64 μM/mg/min and K(m) 1.274%, respectively, while that of sucrose was linear. Partially purified sucrose phosphorylase digested only sucrose. The digestion products were fructose, glucose-1P and free glucose. The reaction was in agreement with Michaelis-Menten kinetics. The V(max) were 0.599 and 0.584 μM/mg/min, while K(m) were 0.190 and 0.202% for fructose release and glucose-1P formation, respectively, when bacteria grew on inulin. The V(max) were, however, 1.37 and 1.023 μM/mg/min, while K(m) were 0.264 and 0.156%, if bacteria were grown on sucrose. The free glucose was hardly detectable for the enzyme originated from inulin grown bacteria, but glucose levels ranged from 0.05 to 0.25 μM/mg/min, when cell extract from bacteria grown on sucrose was used. Release of free glucose was observed when no inorganic phosphate was present in reaction mixture.
The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, ul. Instytucka 3, 05-110 Jablonna, Warsaw, Poland. a.kasperowicz@ifzz.pan.pl
Anna
A
Kasperowicz
Katarzyna
K
Stan-Glasek
Wanda
W
Guczynska
Peter
P
Pristas
Peter
P
Javorsky
Anna
A
Vandzurova
Tadeusz
T
Michalowski
D000818:Animals; D005630:Fructans / Q000378:metabolism; D005632:Fructose / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D005964:Glucosyltransferases / Q000302:isolation & purification / Q000378:metabolism*; D006094:Gram-Positive Bacteria / Q000201:enzymology* / Q000302:isolation & purification; D006868:Hydrolysis; D007444:Inulin / Q000378:metabolism; D007700:Kinetics; D009844:Oligosaccharides / Q000378:metabolism; D031784:Phleum / Q000737:chemistry; D012417:Rumen / Q000382:microbiology*; D013379:Substrate Specificity; D013395:Sucrose / Q000378:metabolism; D043324:beta-Fructofuranosidase / Q000302:isolation & purification / Q000378:metabolism*
D005630:Fructans; D009844:Oligosaccharides; D005632:Fructose; C002938:polyfructosan; D013395:Sucrose; D007444:Inulin; D005964:Glucosyltransferases; C025901:sucrose phosphorylase; D043324:beta-Fructofuranosidase; D005947:Glucose