Transcript Chapter 11c
TORTORA • FUNKE • CASE Microbiology AN INTRODUCTION EIGHTH EDITION B.E Pruitt & Jane J. Stein Chapter 11, part C The Prokaryotes: Domains Bacteria and Archaea The (delta) Proteobacteria Delta Proteobacteria include the genera Myxococcus and Bdellovibrio which prey on other bacteria and Desulfovibrio which are dissimilatory sulfur reducers. The (delta) Proteobacteria • Bdellovibrio. Prey on other bacteria • Desulfovibrionales. Use S instead of O2 as final electron acceptor, form H2S • Myxococcales. Gliding. Cells aggregate to form myxospores The (delta) Proteobacteria Figure 11.10a The (delta) Proteobacteria Figure 11.1b The (epsilon) Proteobacteria Epsilon-proteobacteria include the genera Campylobacter and Helicobacter which are human pathogens The (epsilon) Proteobacteria • Campylobacter • One polar flagellum • Gastroenteritis Figure 11.1a The (epsilon) Proteobacteria • Helicobacter • Multiple flagella • Peptic ulcers • Stomach cancer Figure 11.1b The Nonproteobacteria Gram (-) Sulfur bacteria Other groups that don’t fit anywhere Cyanobacteria • Oxygenic photosynthesis • Gliding motility • Fix nitrogen Cyanobacteria Figure 11.12a-c Anoxygenic Photosynthetic Bacteria • Anoxygenic photosynthesis • Purple and green sulfur bacteria • Chlorobi maybe proteobacteria • Other anoxygenic are non-sulfur purple and green • Use organic compounds light (CH2O) + H2O + O2 2H2O + CO2 2H2S + CO2 light (CH2O) + H2O + 2S0 Assorted other phyla of bacteria -Chlamydiae • Obligate intracellular parasites • Gram(-) • C. trachomatis • Trachoma • STD, urethritis • C. pneumoniae • C. psittaci • Causes psittacosis • Parrots? Wild birds In Bergey's Manual, Volume 5 Figure 11.22a In Bergey's Manual, Volume 5 Figure 11.22b Spirochaetes • Borrelia • Leptospira • Treponema Figure 11.23 Leptosporsis MODE OF TRANSMISSION: Contact of the skin or mucous membranes with contaminated water, soil or vegetation; direct contact with urine or tissues of infected animals; occasionally through ingestion of contaminated food or by inhalation of droplet aerosols of contaminated fluids INCUBATION PERIOD: Usually 10 days with a range of 4-19 days COMMUNICABILITY: Direct transmission from person to person is rare; leptospires may be excreted in urine for usually 1 month but has been observed as long as 11 months after the acute DISSEMINATION RESERVOIR: Farm and pet animals, including cattle, dogs, horses and swine; rats and other rodents act as the normal carrier host; wild animals, including deer, squirrels, foxes, skunks and even reptiles and amphibians may be infected; in Europe, field mice, voles, Shrews and hedgehogs are common reservoirs; in carrier animals, an asymptomatic infection occurs ZOONOSIS: Yes - direct and indirect contact with urine, abortion products, and materials contaminated with urine from infected animals Bacteroidetes • Anaerobic • Bacteroides. In mouth and large intestine • Bacteroides are gram-negative, nonsporeforming, anaerobic, and rod-shaped bacteria • Bacteroides are one of the most numerous of the intestinal bugs and we get to see a great many everyday as about 30 % of what comes out of the intestine is bacteria! 1 billion per gram of feces • Veillonella - hydrogen sulfide producer in mouth • Veillonella are Gram-negative cocci that are the anaerobic counterpart of Neisseria. These non-motile diplococci are part of the normal flora of the mouth. The reason this organism is important is not due to its pathogenicity. Instead, we include Veillonella because it can be and is often mistaken for the more serious gonococcal infection. The most common species isolated from humans is V. parvula. Veillonella species are negative for almost every biochemical test with the exception of an occasional strain being positive for catalase. Fusobacteria • Fusobacterium • Found in mouth • Strict anaerobe • May be involved in dental diseases • Could spread • Lemierre Syndrome Figure 11.24