Page:Bergey's manual of determinative bacteriology.djvu/318

 ring and a blue outer ring. Colonies colored Acid without gas from glucose, galactose, only when well separated and at an optimum maltose, lactose, arabinose and xjdose. salt concentration of 12 per cent. Starch not hydrolyzed. Agar slant (12 per cent salt-1 per cent Nitrites produced from nitrates; no gas proteose peptone-2 per cent KNO3) : Moder- is produced, ate, filiform, slightly raised, smooth, Aerobic. slightly transparent growth with a blue- Optimum temperature, 30° C. brown margin; leaves a colored print in Salt tolerance: Halotolerant, growing in the agar. 0.5 to 30 per cent salt and in Dead Sea water. Broth (12 per cent salt-1 per cent pep- Optimum growth at 12 per cent salt, tone): Very turbid; w*hite pellicle; broth Source: Isolated from the water of the turns brown, the color disappearing after Dead Sea. several days. Habitat: Found in places where the salt Indole not produced. content of water is high. FAMILY III. ACHROMOBACTERACEAE BREED, 1945. (Achromobacteriaceae (sic) Breed, Jour. Bact., 50, 1945, 124.) A.chro.mo.bac.te.ra'ce.ae. M.L. mas.n. Achromohacler type genus of the family; -aceae ending to denote a family; M.L. fem.pl.n. Achromobacteraceae the Achromobacter family. Small to medium-sized rods which are usually uniform in shape. Motile by means of peritrichous flagella or non-motile. Gram-negative. May or may not liquefy gelatin. Growth on agar slants is non-chromogenic to yellow, orange, brown or even red; the pigment does not diffuse through the agar and apparently is carotenoid in nature. May produce acid but no gas from glucose and sometimes from other sugars; lactose is very rarely or never at- tacked. Certain species liquefy agar and/or attack alginates, others digest chitin. May or may not reduce nitrates. Litmus milk may be unchanged, slightly acid (not enough to be curdled) or alkaline. No luminescent species are known. Generally found as salt-water, fresh-water or soil forms, less commonly found as parasites or pathogens. Some plant path- ogens may belong here. Key to the genera of family Achromobacteraceae. I. Do not attack agar, alginates or chitin. Not active in the production of acid from sugars, especially lactose. A. Non-chromogenic on ordinary agar media, although the type species of Achroino- bacter produces yellow chromogenesis on potato. 1. Litmus milk alkaline. No acid from carbohydrates. Genus I. Alcaligenes, p. 297. 2. Litmus milk slightly acid (not enough to be curdled), unchanged or alkaline. Small amounts of acid are usually produced from hexoses. Genus II. Achromobacter, p. 300. B. Yellow, orange, brown or red chromogenesis produced on ordinary agar media; the pigment is non-water-soluble. Genus III. Flavobacterium, p. 309. II. Attack agar, alginates or chitin. Slightly more active in the fermentation of sugars than is the previous group, some even attacking lactose. Non-chromogenic or chromo- genic, usually with yellow or orange, always non-water-soluble pigments. A. Attack agar and/or alginates. Genus IV. Agarbacterium, p. 322. B. Attack chitin and sometimes horny substances. Genus V. Beneckea, p. 328.