Soil Microbial Ecology - Soil Molecular Ecology Laboratory
Soil Microbial Ecology - Soil Molecular Ecology Laboratory
Soil Microbial Ecology - Soil Molecular Ecology Laboratory
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
Page 31<br />
GRAM-NEGATIVE AEROBIC RODS AND COCCI<br />
Pseudomonadaceae<br />
Pseudomonas - straight or curved rods, motile by polar flagella, chemoorganotrophs,<br />
most are strict aerobes (a few species can denitrify), abundant in rhizosphere.<br />
Xanthomonas - straight rods, motile by polar flagellum, growth on agar yellow,<br />
chemoorganotrophs, strict aerobes, mostly plant pathogens.<br />
Azotobacteraceae<br />
Azotobacter - large ovoid to coccoid cells, marked pleomorphism, form thick-walled<br />
cysts and capsular slime, motile with peritrichous flagella or nonmotile, gram-neg. or<br />
variable, fix atmospheric nitrogen.<br />
Beijerinckia - straight to pear-shaped with rounded ends, up to 6 um with occasional<br />
branching, cysts and capsules in some species, produces copious slime in culture,<br />
fixes atmospheric nitrogen, acid tolerant.<br />
Rhizobiaceae<br />
Rhizobium - rods but pleomorphic under adverse conditions, motile by 2 to 6 peritrichous<br />
flagella, nonsporing, copious extracellular slime in culture, chemoorganotrophs,<br />
aerobic to microaerophilic, able to invade root hairs of leguminous plants.<br />
Agrobacterium - rods, motile by 1 to 4 peritrichous flagella, nonsporing, slime<br />
production, chemoorganotrophs, aerobic, most initiate plant hypertrophies.<br />
Uncertain affiliation<br />
Alcaligenes - rods to cocci, motile by up to 4 peritrichous flagella, chemoorganotrophs,<br />
strict aerobes. Saprophytes in animals and soil.<br />
Gram-Negative Facultative Anaerobic Rods<br />
Flavobacterium - coccobacilli to slender rods, motile with peritrichous flagella or<br />
nonmotile, pigmented in culture, chemoorganotrophs, fastidious as to requirement.<br />
Gram-Negative Cocci and Coccobacilli<br />
Acinetobacter - short rods to cocci, large irregular cells and filaments in culture, no<br />
spores or flagella, chemoorganotrophic, strict aerobes, resistant to penicillin.<br />
Gram-Positive Cocci<br />
Micrococci - spherical, non-motile, chemoorganotrophs, aerobic.<br />
Staphylococcus - spherical, chemoorganotrophs, metabolism respiratory or fermentative,<br />
produce extracellular enzymes and toxins, facultative anaerobes.<br />
Streptococcus - spherical to ovoid, chemoorganotrophs, metabolism fermentative,<br />
facultative anaerobes.
Change language