Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
12 Cards in this Set
- Front
- Back
|
Rickettsias
|
Genera: Rickettsia and Wolbachia
Found in: Alpha- and Gammaprotebacteria Small coccoid/rod-shaped bacteria Location: Obligate intracellular parasites Causative agents of several human diseases Oxidizes glutamate or glutamine only. Cannot oxidize glucose or organic acids Transmitted by arthropod vectors |
|
|
Spirilla
|
Genera: Spirillum and Campylobacter
Found in: All 5 classes of Proteobacteria Motile, spiral-shaped bacteria Location: Wide range of environments Classified based on cell shape, size, number of polar flagella, relation to O2, relationship to plants, fermentative ability, & more. |
|
|
Nonsporulating Gram-Positive Bacteria I
|
Genera: Staphylococcus and Micrococcus
Catalase positive organisms with typical respiratory metabolism Distinguished based on oxidation-fermentation test Micrococcus - obligate aerobe, produces acid from glucose only under aerobic conditions Staphylococcus - facultative aerobe, produces acid from glucose both aerobically and anaerobically, is a common parasite of humans and animals S. aureus: yellow-pigmented species associated with pathological conditions S. epidermis: non-pigmented and non-pathogenic organism found on skin and mucous membranes |
|
|
Nonsporulating Gram-Positive Bacteria II
|
Genera: Streptococcus and other cocci
Lactic acid fermenters Streptococcus: Organisms separated by ability to complete blood cell hemolysis through presence of enzyme streptolysin β-hemolysis – large zone of lysis on blood agar plate α-hemolysis – discoloration due to loss of potassium from blood cells (greening) instead of hemolysis |
|
|
Endospore-forming Gram-Positive Bacteria
|
Genera: Bacillus and Clostridium
Distinguished based on cell morphology, shape, endospore position, relationship to O2, and energy metabolism Bacillus: Aerobic or facultative, Important producers of antibiotics (bacitracin, polymyxin, gramicidin), Some species are insect pathogens, Agriculturally important Clostridium: Anaerobic, Obtain energy through substrate-level phosphorylation (most ferment carbohydrates or amino acids), Causes disease in humans (C. botulinum and C. tetani) |
|
|
Actinobacteria I
|
Coryneform and Propionic Acid Bacteria
Genera: Corynebacterium and Propionibacterium High GC-content gram-positive organisms, Very large phylum consisting of over 30 families. Typically rod-shaped or filamentous Inhabit soil and plant materials Corynebacterium: Aerobic, non-motile, irregular rods (club-shaped), Includes animal and plant pathogens Propionibacterium: First discovered in Swiss cheese (fementative production of CO2 produces the characteristic holes in the cheese), Presence of propionic acid following fermentation flavors cheese |
|
|
Actinobacteria II
|
Mycobacterium
Genus: Mycobacterium Rod-shaped organism that may undergo branching or filamentous growth Divided into slow or fast growers Have the ability to form yellow carotenoid pigments and are classified based on this ability (Nonpigmented, pigment formed only when cultured in light: photochromogenesis, pigment formed when cultured in light and darkness: scrotochromogenesis), Stains weakly gram-positive because of presence of mycolic acid in the cell wall (Mycobacteria require acid-fast stain). |
|
|
Cyanobacteria
|
Genera: Synechococcus and Nostoc
Oxygenic, phototrophic Bacteria (first oxygen-evolving organisms on Earth), Closely related to gram-positive bacteria, Possess cyanophycin that functions as a nitrogen storage product. Divided into 5 morphological groups: 1. Unicellular, dividing by binary fission 2. Unicellular, dividing by multiple fission (colonial) 3. Filamentous, containing differentiated cells called heterocysts that function in nitrogen fixation 4. Filamentous nonheterocystous forms 5. Branching filamentous species |
|
|
Chlamydia
|
Genera: Chlamydia and Chlamydophilia
Obligate parasitic bacteria with poor metabolic capacities Chlamydial infections are currently one of the leading STDs Possess gram-negative type cell walls and have both DNA and RNA |
|
|
Spirochetes
|
Genera: Spirocheata and Treponema
Gram-negative, motile, tightly coiled bacteria Widespread in aquatic environments and in animals (many cause diseases, like Syphilis) Classified into 8 genera based on habitat, pathogenecity, phylogeny, and morphological/physiological characteristics |
|
|
Green Nonsulfur Bacteria
|
Genera: Chloroflexus
Thermophilic filamentous bacteria that forms thick microbial mats in neutral to alkaline hot springs Anoxygenic phototroph: contains bacteriochlorophylls a and c and chlorosomes, grows predominantly by photoautotrophy, but can grow in the dark as a chemoorganotroph by aerobic respiration Modern relative of early phototrophs: most ancient of anoxygenic phototrophs |
|
|
Hyperthermophilic Bacteria
|
Genera: Thermatoga and Thermodesulfobacterium
Found: close to root of universal tree of life Grows optimally at temp. above 80 degrees C Thermatoga: Rod-shaped organism that grows best at 80 degrees C, contain a sheathlike envelope called a toga, stain gram-negatively, nonsporulating, anaerobic, fermentative chemoorganotroph, has many genes in common with hyperthermophilic Archaea Thermodesulfobacterium: sulfate-reducing bacterium, strict anaerobe, presence of ether-linked lipids, which is a hallmark of Archaea |
