Disaccharide preference of an aerobic cellulolytic bacterium, Cellvibrio gilvus n. sp.

A distinct preference for cellobiose over glucose has been reported frequently among cellulolytic bacteria (Hutchinson and Clayton, 1918; Enebo, 1949; McBee, 1948; Hungate, 1950; Sijpesteijn, 1951; Hall, 1952), yet little attention has been given to the elucidation of this phenomenon. Recently, Sih and McBee (1955), and Sih et al. (1957), reported certain characteristics of a cellobiose phosphorylase which seemed to initiate cellobiose metabolism in Clostridium thermocellum. This organism does, however, possess an intracellular hexokinase, and it has not been possible to explain the reason for growth failure in media containing glucose. Other investigations of direct utilization of disaccharides by microorganisms have been reviewed by Hestrin (1949), Gottschalk (1949), Doudoroff (1951), and Deley and Bernaerts (1953). Although these studies have contributed materially to many facets of sugar metabolism, they have not elucidated the reason(s) for disaccharide preference in even a single organism. Recently, Doudoroff et al. (1956) presented new information relative to the enzymatic basis for the inability of the "wild strain" of Pseudomonas saccharophila to grow on glucose and fructose. The present report concerns the demonstration of a disaccharide preference by an aerobic cellulolytic organism, Cellvibrio giltus n. sp.