Ilyobacter polytropus DSM 2926

Ilyobacter polytropus (strain DSM 2926 / CuHBu1) is a strictly anaerobic, chemoorganotroph, non spore-forming Gram-negative bacterium isolated from marine anoxic mud in Cuxhaven, Germany. The cells are generally rod-shaped (0.7-1.5-3.0 um) with rounded ends and show irregularly elongated rods, when grown on glucose and fructose containing media. They are usually arranged in pairs or chains. The organism is nonmotile and no flagellar genes have been found in the genome. I.polytropus also grows in salt water medium or brackish water medium containing 1% NaCl and 0.15% MgCl2.6H2O. Phosphate (up to 50 mM) does not inhibit growth of I. polytropus, when grown on 3-hydroxybutyrate. The temperature range for growth is between 10 and 35 degrees Celsius, with an optimum at 30 degrees Celsius. The organism does not grow at 4 or at 40 degrees Celsius . The pH range for growth is between 6.5-8.5, with an optimum at pH 7.0-7.5. I. polytropus shows acetate kinase, phosphate acetyl transferase and hydrogenase activities, which are sufficient for involvement in dissimilatory metabolism. I. polytropus maintains its energy metabolism exclusively by substrate-linked phosphorylation reactions. It differs from other anaerobes because it exhibits broad versatility in its use of various fermentation pathways. It is able to ferment 3-hydroxybutyrate and crotonate to acetate and butyrate, glycerol to 1,3-propanediol and 3-hydroxypropionate, malate and fumarate to acetate, formate and propionate, and glucose and fructose to acetate, formate and ethanol. It is also able to ferment a variety of sugars and organic acids. However, pathway regulation is reported as enigmatic because neither propionate nor butyrate are formed during glucose or fructose fermentation, although the necessary enzymes are present. I. polytropus is of ecological interest because the organism does not degrade poly-hydroxybutyrate but only the monomeric form of 3-hydroxybutyrate. Metabolism of the polymer appears to be confined to aerobic microbial communities. (Adapted from: http://standardsingenomics.org/index.php/sigen/article/view/sigs.1273360). (EBI Integr8)