Acinetobacter ca,lcoiccet,icus 69-V is not able to grow on carbohydrates or its derivat,ives and to u s e them 0 s sole carbon sources. On the other hand, the partial oxidation of several monosaccharidtv (glucose, galactose, mannose, xylose, arabinose, ribose) by intact cells has been denionst'rnted by acid production and measurements of oxygen consumption.
Glucose and fructose are taken up by intact cells. Different transport, systems exist for t.hc riptakc of both hexoses. The "apparent" Knpvalues for the membrane transport amount to 1.5 . lo-;% and 1.7 .
rnoles/l for glucose and fructose, respectively. Gluconolacton only inhibit,s t.he t.riinsport of glucose, whcreas the transport of both hexoses is inhibited by nranylwettkte. 0t)her monosaccharides and metabolic inhibitors arc without effect. ,4n exchange of intracellular ag;iirist, extracellular glucose has not been found.
Gluconatc and CO, have been identified as extracellular products of glucose oxidation after an incubat>ion period of more t,han 5 min, whereas gluconate and 6-phosphogluconate have been detected i ~a intracellular products. No oxidation products have bccn found using fructose as substrat,e.
KO activity of hexokinase, phosphofructokimse, pyruvate kinase, and 6-phosphoglnconat,e dehydrogenase have been detected in cell-free extracts of sonicated cells. An aldose dehydrogenwe coupled with an electron transport system occurs in the membrane fraction. The presence: of this cneyme was demonstrated by the reduction of dichlorophcnolindophenol as well as by oxygen consumption which is inhibited by cyanide. The aldose dehydrogenase exhibits t i broad substrate specificity against different aldohexosrs and aldopentoses differing by their Knr-values. Cytochrome b and the terminal oxidase cyt,ochronic o are components of the electron transport, system. Neither hydrogen peroxide is formrd. n o r pyridinc nucleotides pa.rticipate in aldose dehydrogenation.