Moraxella acinetobacter veillonella metabolism

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- Moraxella - Acinetobacter - Veillonella Metabolism - oxidizes glucose (only) to acids - fastidious > capnophilic (4-8% CO 2 ) > will not grow at 22 o C; prefers 30-37 o C > susceptible to cold, heat & drying Other Unique Features - *NATURAL TRANSFORMER* > highly autolytic @ stationary phase * know mech of invasion!!! Virulence - no capsule - pili: antiphagocytic & attach to columnar epi > necessary for DNA uptake (transformation) > exhibit antigenic variation - porins (Por A, B) translocate to host membranes to induce epi cells to ingest them - Rmp (a surface protein) > Ag for prod of IgG blocking Ab V (anti IgM, anti C’) - lipooligosaccharide (LOS) V damages cilia → sloughing > exhibits antigenic variation > target of IgM antibody - IgA protease V - steals Fe + from transferrin, lactoferrin & Hb Opa : adherence > antigenic var (+) = opaque, local disease (-) = transparent, Disseminated GI porins can be used for serotyping b/c invariable COMPARE to N. meningitidis Transmission - venereal infxn usu. acquired via GU epithelium - Risk factors : sexual partners, age (peaks at 15-24, 25- 30), blocking Ab , terminal C’ factor deficiency - endemic disease Associated Diseases In * Urethritis (only ~10% aSx) * Epididymitis In (50% are aSx) * Cervicitis * Salpingitis * Pelvic Inflammatory Disease (15-20%) * Disseminated gonococcal infection (rare) - polyarthralgia, tenosynovitis, dermatitis/septic arthritis - pustular, erythematous lesions Future test: nucleic acid hybridization Diagnosis : GC on Gram stain is diagnostic : need culture of cervical pus to make diagnosis In use Thayer Martin media, kill off normal flora Treatment(s) * ß-lactam & tetracycline resistant > plasmid-encoded ß-lactamase > chromosomally-mediated in OM permeability * Cephtriaxone (IM), Cefixime (oral) or a quinolone > single dose for better patient compliance
Neisseria diplococci inside of WBCs from peripheral blood smear
More to come next quarter Chlamydia trachomitis Lab ID little or no cell wall (but may be considered G- ) Metabolism - “ Energy parasite ” (cannot make ATP) > imports nutrients from cytosol into endosome via tubular projections (like a Type III secretory system ) Other Unique Features OBLIGATE INTRACELLULAR PARASITE > prevents phago-lysosome fusion > lives in phagosome - Life Cycle involves: > elementary body (EB) : round w/strong spore-like coat > reticulate body (RB) : replicative form; analogous to bacterial cell - causes persistent and recurrent infxns -EB attaches to host R parasite specified endocytosis -EB differentiates into RB → binary fission - condense DNA, disulfide bridge of MOMP → EB s are released Virulence Transmission - 1 o host = humans - main vector = common house fly > disease of underprivileged w/poor hygiene - 2 biovars (based on target cells) > biovar trachoma squamocolumnar cells of eye & GU tract, conjunctivitis in primates > biovar lymphogranuloma venereum (LBV) infects inguinal LNs LV Chronic conjunt Serovars A, B, C Oculogenital dis Serovars D, E, F, G,( B, C, H, I, K) Injection of LBV intracerebrally in mice is lethal!

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