FAMILY MYXOCOCCACEAE 



1049 



1 . Sporocytophaga myxococcoides 



(Krzemieniewska Stanier. {Spirochaeta 

 cytophaga Hutchinson and Clayton, 

 Jour. Agr. Sci., 9, 1919, 150; Cyto- 

 phaga myxococcoides Krzemieniewska, 

 Arch. Mikrobiol., 4, 1933, 400; Cytophaga 

 globulosa Stapp and Bortels, Cent. f. 

 Bakt., II Abt., 90, 1934, 47; Cytophaga 

 hutchinsonii Imsenecki and Solntzeva, 

 Bull. Acad. Sci. U.S.S.R., Ser. Biol., 

 Xo. 6, 1936, 1129; not Cytophaga hutchin- 

 soni Winogradsky, Ann. Inst. Pasteur, 

 4S, 1929, 578; Stanier, Jour. Bact., 40, 

 1940, 630.) 



Etymology : Modern Latin from generic 

 name Myxococcus, and eidos, like. 



Vegetative morphology: Flexible, singly 

 occurring rods, 0.3 to 0.4 micron wide 

 at the center, tapering to both ends. 

 Length 3 to 8 microns according to 

 Krzemieniewska {loc. cit.), 2.5 to 5 

 microns according to Jensen (Proc. Linn. 

 Soc. X.So. Wales, 65, 1940, 547). May be 

 straight, bent, U-shaped or S-shaped. 

 Show creeping motility (Stapp and 

 Bortels, loc. cit.). Stain poorly with 

 ordinarj^ aniline dyes; with Giemsa's 

 stain, the young cells are colored uni- 

 formly except for the tips. As the rods 

 shorten and swell to form microcysts, the 

 chromatin becomes concentrated and 

 moves toward the center of the cell, 

 generally in the form of two parallel 

 bands (Krzemieniewska, Acta Soc. Bot. 

 Pol., 7, 1930, 514). 



Microcysts: Spherical, 1.3 to 1.6 

 microns in diameter, covered with a 

 sheath of mucus. According to Krze- 

 mieniewska (1930, loc. cit.), germination 

 is by emergence of the shortened rod 

 from the sheath, followed by elongation; 

 according to Stapp and Bortels {loc. cit.) 

 and Imsenecki and Solntzeva (loc. cit.), 

 by a simple elongation of the entire 

 microcyst. 



Growth is strictly confined to cellulose. 

 On mineral salts-silica gel plates covered 

 with filter paper, yellow, glistening, 

 slightly mucilaginous patches are pro- 



duced after a few days. The color 

 gradually assumes a light brownish tinge 

 on aging. The filter paper in these 

 regions is eventually completely dis- 

 solved and the patches become trans- 

 lucent. 



Ammonia, nitrate, asparagin, aspartic 

 acid and peptone can serve as sources of 

 nitrogen (Jensen, loc. cit.). 



Strictly aerobic. 



Optimum temperature 28 to 30 °C. 



Source : Isolated from soil . 



Habitat: Soil. Decomposes cellulose. 



2. Sporocytophaga congregata Fuller 

 and Xorman. (Jour. Bact., 4-5, 1943, 

 567.) 



Etymolog}' : Latin congrego, to as- 

 semble. 



Vegetative cells are long, fiexuous rods 

 with pointed ends, 0.5 to 0.7 by 5.5 to 



8.0 microns. Creeping motility on solid 

 surfaces. 



Spores (microcysts) : Spherical, 0.7 to 



1.1 microns in diameter. Usually occur 

 in localized regions within the colony. 



Growth on starch agar is smoky, later 

 turning yellow. Colonies are irregularly 

 round, slightly concave. Edge is smooth 

 and entire at first, later becoming irregu- 

 lar. Marginal and internal swarming 

 may be prominent. The vegetative 

 cells gather into groups and in these 

 regions a large number of spherical 

 spores are found. 



Growth on cellulose dextrin agar is 

 pale; colonies are small and concave. 

 Hollowing of the agar is limited to the 

 area of colony growth. 



Glucose, galactose, lactose, maltose, 

 sucrose, arabinose, calcium gluconate, 

 starch, cellulose dextrin, pectin, and 

 hemicellulose are utilized. Filter paper 

 is not attacked. 



Ammonium, nitrate, and peptone are 

 suitable nitrogen sources. 



Indole not formed. 



Xitrites not produced from nitrates. 



