Bacterial Survey Gram negatives 2 Aerobic bacilli and

Bacterial Survey – Gram negatives 2) Aerobic bacilli and cocci • Pseudomonas • Legionella • Neisseria • Rhizobium • Agrobacterium • Methanobacterium

Pseudomonas • Large taxon; K/K on TSI • “garbage disposals” of the MO world • Ubiquitous; assoc. with nosocomial infections • Resistance and virulence factors/traits • Opportunistic; can affect compromised hosts – Burn patients – Cancer patients – Transplant patients

Legionella • Recently discovered (1976) at Legionnaire’s convention • Found in cool waters • Transported by aerosols • Produces mild-severe respiratory infections – High fever, cough • Diagnosis by immunoflourescence

Neisseria I • Diplococci diagnostic • N. gonorrhoeae – produces urethritis –> cystitis -> pyelonephritis • 80% males show signs • Female signs inconsistent • Dysuria, polyuria, pyuria • Ascending infections – Vas deferens blocked – PID • Systemic infections – Gonorrheal endocarditis – Gonorrheal arthritis – Eyes/pharynx – opthalmia neonate Co-infections with Chlamydia

Neisseria II • N. meningitidis – causes ~30% of childhood meningitis • Initiates as throat infection -> sepsis -> meningitis • Endotoxin effects to blood-brain barrier • High mortality

Rhizobium • symbiotic N 2 -fixer in the roots of legumes (clover, alfalfa, vetch, peas, beans) • Expresses nitrogenase at low O 2 tension in roots • Reduces N 2 NH 2 for incorp into amino acids • Major route for N into the biosphere Root nodules on legume species

Agrobacterium • associative N 2 -fixer • Plant pathogen – causes “crown gall” • produced by Ti (tumorinducing) plasmid • Ti plasmid is used as a DNA vector in biotechnology – nitrogenase genes – other genes