FAMILY VII. MICROCOCCACEAE 



457 



mann and Neumann, Bakt. Diag., 1 Aufi., 

 S, 1896, 161.) 



lu'te.us. L. adj. luteus golden-yellow. 



Spheres, 1.0 to 1.2 microns in diameter, 

 occurring in pairs and fours. Non-motile. 

 Gram-positive. 



Gelatin colonies: Yellowish white to yel- 

 low, raised, with undulate margin. 



Gelatin stab: No liquefaction (Schroeter, 

 in Cohn, Krj^ptog. Flora v. Schlesien, 3, I, 

 1886, 144). 



Agar colonies: Small, yellowish, glisten- 

 ing, raised. 



Agar slant: Citron-yellow, smooth 

 growth. 



Broth: Clear, with yellowish sediment. 



Litmus milk: Usually slightly acid, not 

 coagulated. 



Potato: Thin, glistening, citron-yellow 

 growth. 



Indole not produced. 



Acid from glucose, sucrose and mannitol. 

 No acid from lactose. 



Starch not hydrolyzed. 



Nitrites not produced from nitrates. 



Ammonia produced from peptone. 



Utilizes NH4H2PO4 as a source of nitro- 

 gen; also utilizes ammonium tartrate, 

 growth occurring after 6 weeks in Cohn's 

 solution (Cohn, op. cit., 1872, 153). 



Saprophytic. 



Aerobic. 



Optimum temperature, 25° C. (Eisenberg, 

 Bakt. Diag., 1891, 39). 



Comments: It is recommended that Cul- 

 ture number 398, Micrococcus luteus, of the 

 American Type Culture Collection be ac- 

 cepted as the type culture for this species. 

 This culture has been retested (September, 

 1955) and has been found to grow slowly in 

 Cohn's solution without added sugar after 

 6 weeks under conditions similar to those 

 used by Cohn in 1872. On reinoculation, this 

 culture now develops within 2 weeks in 

 Cohn's solution. 



Source: Isolated by Schroeter from dust 

 contaminations on cooked potato. 



Habitat: Found in milk and dairy pro- 

 ducts and on dust particles. 



2. Micrococcus ureae Cohn, 1872. (Bei- 



triige z. Biol. d. Pflanzen, 1, Heft 2, 1872, 

 158.) 



u're.ae. Gr. noun ururn urine; M.L. noun 

 tirea urea; M.L. gen. noun ureae of urea. 



Spheres, 0.8 to 1.0 micron in diameter, oc- 

 curring singly, in pairs and in clumps. Never 

 in chains. Non-motile. Gram-variable. 



Gelatin colonies: Small, white, translu- 

 cent, slimy, becoming fissured. 



Gelatin stab: Slight, white growth. Very 

 slow or no liquefaction. 



Agar colonies: White, slightly raised. 



Agar slant: Grayish white, raised, glisten- 

 ing, butyrous growth. 



Broth: Turbid, with viscid sediment. 



Litmus milk: Slightly alkaline; litmus 

 slowly reduced. 



Milk: Acid. 



Potato: Slight, grayish to pale olive 

 growth. 



Indole not produced. 



Acid produced from glucose, lactose, 

 sucrose and mannitol. 



Starch not hydrolyzed. 



Nitrites not produced from nitrates. 



Urea fermented to ammonium carbonate. 



Ammonium salts are utilized. 



Ammonia produced from peptone. 



Saprophytic. 



Aerobic. 



Optimum temperature, 25° C. 



Source: Isolated from fermenting urine. 



Habitat : Found in stale urine and in soil 

 containing urine. 



3. Micrococcus freudenreichii Guille- 

 beau, 1891. (Landwirtsch. Jahrb. d. Schweiz, 

 5, 1891, 135.) 



freud.en.reich'i.i. M.L. gen. noun freu- 

 denreichii of Freudenreich; named for E. 

 von Freudenreich, a Swiss bacteriologist. 



Spheres, 2.0 microns in diameter, occur- 

 ring singly and in clumps, rarely in short 

 chains. Non-motile. Gram-positive. 



Milk gelatin colonies: Small, white, 

 opaque. 



Milk gelatin stab : Infundibuliform lique- 

 faction. 



Agar colonies: White, slimy. 



Agar streak: White, smooth growth. 



Broth: Turbid, with white sediment. 



