Staphylococcus Species
Cytolytic toxins
A,B, Y, o and leukocidin all break up the cell membrane of their target cells. Are all proteins and are coded by chromosomal genes not plasmid genes
What is the treatment of staphylococcus?
Antibiotics but hard to do because of MRSA and VRSA
Staphylococcal food poisoning
Caused by Staphylococcus aureus; grow in contaminated food and release its toxins, individual invests the toxins; symptoms begin 2hrs after and end in 24 hrs; vomiting and diarrhea are the usual symptoms
Pyroderma
Caused by staphylococcus and produced puss
What are pathogenic staphylococcus aureus?
Coagulase positive, DNase positive, ferment mannitol
What enzymes are important for staphylococcus?
Coagulase; hyaluronidase; staphylokinase; lipase; B lactamase
What are some examples of high guanine and cytosine pathogens in a genera?
Corynebacterium; mycobacterium, propionibacteria, nocardia, actinomyces
What are the four categories of toxins produced by staphylococcus aureus?
Cytolytic toxins, exfoliative toxins, enterotoxins
Enterotoxins
Five proteins which cause the symptoms of staphylococcal food poisoning. Include nausea, vomiting, stomach cramps and diarrhea
What is the structure and physiology of staphylococcus?
Gram positive, facultative anaerobes, non motile, facultative halophiles, catalase positive , more resistant to heat and drying
Toxemia
Scalded skin syndrome; skin becomes extremely red and scales off.
What are the methods used to interfere with phagocytosis?
Inactivate the opsonization effect of IgG through protein A; production of enzyme coagulase; production of slime layer
endocarditis
Infection of the tissue lining the heart; including the valves and often fatal due to decreased heart function
pneumonia and empyema
Inflammatory lung infections; caused by staphylococci Pus in fluid= empyema Clear fluid= pneumonia
Staphylococcus pathogenicity
Interference with phagocytosis; enzymes that enhance the ability of an organism to invade host tissue; toxins
What is the diagnosis of staphylococcus?
Made by identification from a culture, identified by rapid ID methods, based on coagulase status
Where is staphylococcus found?
Normal microbiota and on the skin. Respiratory tract, gastrointestinal tract, urogenital tract
What does staphylococcus epidermis cause?
Opportunist infections
What is the cell wall type for a gram positive cell?
Phylum Furmicutes with two major dicisions depending on the amount of guanine and cytosine in the DNA
Toxic shock syndrome
Potentially fatal infection due to a toxin that caused low blood pressure, fever, diarrhea, rash and shedding of skin; caused by staphylococcus aureus - tampons and contraceptive sponge
What are some examples of low guanine and cytosine in the DNA
Staphylococcus; Streptococcus; enterococcus; bacillus, clostridium, listeria
What are some staphylococcal infections?
Sties, folliculitis, carbuncles, furuncles, pyroderma, impetigo, toxemia
Exfoliative toxins
They are two proteins that act as exfoliative toxins. They breakdown the desmosomes that hold epithelial cells together. They're active in staphylococcal scaled skin syndrome and causes the layer of the skin to slough off.
What does staphylococcus saprophyticus cause?
Urinary Tracy infections
Bacteremia
bacteria in the blood; nosocomial and most begin as a skin infection
Osteomyelitis
inflammation of bone and bone marrow
Impetigo
superficial skin infection characterized by pustules and caused by either staphylococci or streptococci; highly contagious
