Hexokinase of the rumen microorganism Quins Oval : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in the University of Canterbury [Lincoln College]

Abstract

Quin (1943) first noted that the characteristic large gas production observed in sheep fed on high sugar diets of green lucerne, lucerne hay & molasses, was due in the main to the rumen microorganism – Quins Oval – which was found in large numbers in the rumen of such sheep. He observed rapid gas production with preparations of these organisms when they were incubated with glucose. McGaughey & Sellers (1948) also found that Quins Oval (QO) became predominant when sheep were fed hay supplemented with mangolds.

Recent studies by Wicken & Howard (1967) on the cell wall of this organism are consistent with classification of it as a Gram-negative bacterium. Fermentation studies by Brought.et.al (1970) have indicated that suspensions of QO fermented glucose, fructose & sucrose rapidly, mannitol moderately quickly, maltose slowly, but had no action on a number of other mono- & oligo-saccharides & starch. The present work was undertaken to determine whether there were kinases present in cell-free extracts of QO capable of phosphorylating certain monosaccharides that had been shown to have been fermented by this organism. Further work involved purification of a hexokinase from QO & comparison of the properties of this enzyme with those of hexokinases from other organisms.