Short rods, 0.5 by 1.0 to 2.0 microns. Motile by means of six to eight long flagella. Gram-negative.
Gelatin stab: Slow liquefaction. No chromogenesis.
Thiosulfate agar: Colonies small, white, 1 mm in diameter.
Thiosulfate liquid medium: Very little visible turbidity, no sulfur precipitated. Produces sulfate and tetrathionate with increase in pH. Rate of thiosulfate oxidation increased by presence of organic compounds.
No acid or gas from sugars.
Nitrites and gas produced from nitrate-peptone broth; no ammonia produced. May live anaerobically in the presence of nitrates.
Indole not produced.
Hydrogen sulfide not produced.
Starch is hydrolyzed.
Lipolytic.
Catalase-positive.
Non-hemolytic.
Temperature relations: Optimum, 27° C. Minimum, 6.9° C. Maximum, between 36.5° and 40° C. Death occurs in 2 to 5 minutes at 55° C.
Optimum pH, between 7.9 and 8.5. pH limits, 6.0 and 10.0.
Comments: Trautwein (Cent. f. Bakt., II Abt., 61, 1924, 5) regards his bacterium as being closely related to the fluorescent group and to the denitrifying bacteria of Burri and Stutzer. Starkey (Jour. Gen. Physiol., 18, 1935, 346) reports this species to be heterotrophic. However, Lehmann (in Lehmann and Neumann, Bakt. Diag., 7 Aufl., 2, 1927, 516), under whom Trautwein did his work, reports that this species is a facultative autotroph as does Parker also (Jour. Gen. Microbiol., 3, 1953, 344). As facultatively autotrophic species are included in Thiobacillus as defined, this species has again been included in Thiobacillus (see Manual, 2nd ed., 1925, 39). Starkey's culture B and Parker's M culures appear to be identical with Thiobacillus trautweinii.
Source: Isolated from soil and water (Trautwein) and from purified sewage from Würzburg (Lehmann).
Habitat: Widely distributed in polluted waters and soil.
FAMILY IV. PSEUDOMONADACEAE WINSLOW ET AL., 1917.
(Winslow, Broadhurst, Buchanan, Krumwiede, Rogers and Smith, Jour. Bact., 2, 1917, 555.)
Pseu.do.mo.na.da′ce.ae. M.L. fem. n. Pseudomonas type genus of the family; -aceae ending to denote a family; M.L. fem. pl. n. Pseudomonadaceae the Pseudomonas family.
Cells elongate, straight rods, occasionally coccoid. Motile by means of polar flagella which are either single or in small or large tufts. A few species are non-motile. Gram-negative. May possess either water-soluble pigments that diffuse through the medium or non-water-soluble pigments. Usually grow well and fairly rapidly on the surface of culture media. Aerobic. Frequently oxidative in their physiology but may be fermentative. Usually found in soil or water, including sea water or even heavy brines. Many plant and a few animal pathogens.
Key to the genera of family Pseudomonadaceae.
I. Attack glucose and other sugars either oxidatively or fermentatively.
- A. Genera in which the species are either known or are thought to attack glucose oxidatively.
- 1. Bacteria which do not produce readily detectable acetic acid though they may oxidize ethanol. May produce a water-soluble pigment which diffuses through the medium.
- a. Cultures may or may not produce a water-soluble pigment which is bluish, greenish or brownish in color. Rose, lilac- and yellow-colored, diffusible pigments occasionally occur.
