Caulobacter and Hyphomicrobium are aquatic an do not cause human disease f. Rhizobium and Agrobacterium are symbiotic on the roots of leguminous plants. Several important pathogens are in this group. Cause of whooping cough. N. gonorrhea causes gonorrhea and N. meningitidis is a cause of meningitis. Fig 11.6 3.
Pseudomonads are common in soil and water and can live on a wide variety of substrates.
Some are psychrophiles. Legionellales Legionella pneumophiles causes a pneumonia in humans. Slightly curved, gram negative rods, found mostly in aquatic habitats Vibrio cholera causes a severe diarrhea and V. parahemolyticus causes a less severe gastroenteritis. Commonly called enterics. Salmonella commonly inhabit intestines of poultry and cattle.