Lecture Exam 3 Flashcards
Proteobacteria
Gram negative
Based on rRNA sequences
Derived from photosynthetic ancestors
Alpha proteobacteria
Azospirilum Rhizobium Nitrobacter Rickeitsia Rickeitsia rickettsii Brucella Brucella abortus Brucella melitensis Wolbachia
Azospirilum
Soil organism
Nitrogen fixer
Symbiotic fixation; with roots of tropical grasses (corn)
Rhizobium
Soil organism
Nitrogen fixer
Symbiotic with legumes (beans, peas, clover, etc)
Nitrobacter
Soil organism
Not symbiotic
Chemoautotroph- using in organic compounds as its energy source
Take ammonia (NH3) or NO2 to NO3 (nitrification)
Rickeitsia
Rods/coccbicilli
Obligate intercellular parasite- cannot live outside of host cells
Requires an insect or tick as a vector (animal that carries it)
Rickeitsia rickettsii
Rocky Mountain spotted fever Vectored by ticks More common in the southeastern US Symptoms: rash on palm and soles, fever, headache Does respond to antibiotic therapy No vaccine
Brucella
Coccobicillic- no flagella
Obligate parasite of mammals
Zoonose- animal reservoir of disease
Aerobic
Brucella abortus
Also known as Brucellosis
Causes cattle to spontaneous miscarry
Infects cattle, deer, elk, and bison
Brucella melitensis
Causes disease in humans Causes undulant fever Dairy, goats, sheep Undulating fever- night sweats, aches and pains, fever goes up then down then up Responds to antibiotics
Wolbachia
Obligate intercellular parasite
In insects
Very common
Affects the reproduction of the insect. Can cause more eggs, no change, or less eggs
Complex
*release of infected mosquitoes to control Zika and dengue fever
Beta proteobacteria
Bordella pertussis
Neisseria
N. Meningititis
Bordella pertussis
Coccobacilli
Capsule
Causes whooping cough (produces toxins that kill off the cillia in the trachea, mucous accumulate in lungs, and can go systemic)
Starts as cold symptoms, but becomes violent coughing with “whooping” inhalation
Can last weeks
Can kill infants, adults can be asymptotic
Can result in brain damaged kids
Does respond to antibiotics if caught early but not late
There is a vaccine for it
Neisseria
Diplococcus
Has fimbriae- used for attachment to mucous membranes
Neisseria gonorrhoeae- causes gonorrhea- STD “the clap”
-attacks mucosa of the urogenital track, oral cavity, anal, conjunctiva of the eye
- spread mainly by males
- diagnosed by pus discharge in males
- females it’s often asymptotic
-• can affect the cervix and cause reproductive issues
-• can cause pelvic inflammatory disease
- does respond to antibiotics but developing a resistance
- no developed immunity, can get it more than once
N. Meningitis
Diplococcus
Bacterial megingitis
40% of the population has it in their nose (asymptotic carriers)
Bacteremia to bacteria in blood stream, which produces a variety of toxins that result in a headache, that then produces a stiff neck, then a coma, then death. All of that can happen in hours
Usually hits infants under 2 years old
Does respond to antibiotics, but has to be caught quickly
Deaf and brain damage
Gamma proteobacteria
Legionella
Pseudomonas
P. Aeruginosa
Vibrio cholerae
Legionella
Sometimes called “legionare’s disease”
Symptoms are those of pneumonia (causes pneumonia)
Causes by contaminated water supplies aerosols
Difficult to culture
Pseudomonas
Gram negative rods Have polar flagella Common in various environments (water and soil) They are diverse Some cause plant diseases One metabolic trick is they can digest unusual carbon sources Antibiotic resistant Not normally pathogenic
P. Aeruginosa
If you have a wound, especially burns, it will get in there
Abcesses- nor on pets
Urinary tract infections
You can get septicemia to toxins in blood to toxic shock syndrome
Vibrio cholerae
Curved rods- vibrio
It is a facultative anaerobe
Produces an exotoxin in your small intestine
Exotoxin stimulates secretion of water and electrocytes
DFH- 10-20 liters a day, can kill you even if you stay hydrated, physicians refer to this as “rice water stool”
Common inhabitants of brackish (salty water that is not salty enough to keep from drinking) water and fresh water
What killed most of the people on the Oregon trail
Enterics
Gram negative rods Facultative anaerobes Fermenters They tend to have fibriae Attached to the intestines E. Coli Salmonella enterica Yersiha enterocolitica
E. Coli
Normally it’s ok Capable of causing mild diarrhea We use E. Coli as an indicator of food and water contamination But there is a stain of e. Coli called 0157: H2. It will kill you - produces an endotoxin - “enterohemorrhagic” - DFH - most commonly kills elderly and kids - in apple juice by contamination
Salmonella enterica
Difficult genus to classify
High genetic diversity
Use serovaris to diagnose them (identified with antibodies)
Dont normally find it in our intestines, but in birds and reptiles
Common source of food poisoning
Sometimes called “salmonellosis” and non-typhoidal- DFH
typhoidal-
-causes typhoid fever
- serovaris: S. Typhi
- is not carried by birds (not a zoonose)
- human to human- contact and food
- gets inside of white blood cells and spreads
- 2-3 week incubation period
- • fever headache, ulcerated intestines
- will kill people
- can have asymptotic carriers- likes to settle into the gallbladder
-“Typhoid Mary”- Boston in the early 1900s she was a domestic worker, everyone got typhoid fever.
- early study in Epidemiology
Y. Enterocolitica
In the intestines from domestic animals Food contamination Psycherotroph- will grow in the fridge Fever, diarrhea, abdominal pain, etc Can last 2 weeks
Firmicutes
Low G+C ratio
Rods and produce endospores
Bacillus- facultative anaerobe, non- motile, endospores
B. Anthracis
Anthrax Soil and livestock Cutaneous form- “coal black lesions” Pulmonary/lung- 100% mortality rate Gastrointestinal
B. Cereus
Food poisoning
Produce toxins- spores
Diarrhea (most common in restaurant rice)
B. Thuringiensis
Produces a toxin- Bt toxin (protein)
Kills caterpillars
Biocontrol- harmless to humans- kills bugs
Genetically modified organisms
- corn and few other crops to produce the Bt toxin
