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• coccus


  spherical
• bacillus


  rod shaped
• vibrio


  comma shaped
• spirochete


  spiraled shaped
• pleomorphic


  changes shape and size
• plasma membrane


  exterior layer surrounding cells; selectively permeable and regulates which molecules are allowed to enter and exit the cell
• peptidoglycan layer


  the backbone of the cell wall which offers rigidity and strength; thick in gram + bacteria which retains strains
• periplasm


  a concentrated gel-like matrix in the space between the inner cytoplasmic membrane and the bacterial outer membrane in gram-negative bacteria
• outer membrane 


  LPS/endotoxin, porins (form channels for nutrients to pass into cytoplasm), found in gram negative bacteria
• capsule


  protects bacterial cells from engulfment by macrophages and allows for adherence
• sex pilus


  aka conjugative pili; allow for the transfer of DNA between bacteria
• flagella


  allows for movement of cell to more favorable locations
• spores


  highly resistant to environmental stresses, can remain viable for many years, form under unfavorable growth conditions
• beta-lactams


  includes penicillins and cephalosporins; bind to penicillin binding proteins (transpeptidase) to inhibit peptidoglycan (cell wall) synthesis
• rifampin


  inhibits transcription (RNA polymerase inhibitor) by misreading ribosomes
• tetracyclines, aminoglycosides, chloramphenicol, and erythromycin inhibit protein synthesis
• vancomycin


  binds to D-Ala-D-Ala to prevent cell wall synthesis
• fluoroquinolones 


  inhibits DNA replication via gyrase or topoisomerase (inhibits the ability to fit and package the DNA in its cell) thereby inhibiting nucleic acid synthesis
• trimethoprim/sulfa

  inhibits folic acid synthesis thereby inhibiting metabolic pathways
• Are beta-lactam antibiotics effective against mycoplasma?

  No, mycoplasmas do not have peptidoglycan so it is not effective
• minimum inhibitory concentration (MIC)


  the lowest concentration of an antimicrobial drug that will inhibit the visible growth of a microorganism after overnight incubation
• kirby-bauer test

  uses antibiotic-containing wafers or disks to test whether particular bacteria are susceptible to specific antibiotics
• minimal inhibitory concentration


  lowest concentration of a drug that will successfully prevent the growth of an organism
• therapeutic dose


  minimum dose of a drug per kg body weight that stops pathogen growth
• toxic dose 


  maximum dose of a drug tolerated by a patient
• lethal dose


  the amount of a drug that, if administered will prove to be fatal
• infectious dose 50


  the dose of a pathogen required to infect 50% of the population
• lethal dose 50


  the dose of a pathogen required to kill 50% of the population
• innate immunity

  • non-specific, immediate response to pathogensSpecificity for microbial patterns
  • Limited diversity
  • Operates continuously from the time of infection through the incubation
  • period and until the infection ends
  • Essentially made up of barriers that aim to keep viruses, bacteria, parasites, and other foreign particles out of your body or limit their ability to spread and move throughout the body upon entry
• macrophages 


  engulf and digest foreign particles and present antigens to other immune cells
• neutrophils 


  first cells to arrive at the site of infection and kill harmful bacteria
• dendritic cells


  presents antigens to T cells and B cells
• adaptive immunity

  • antigen-specific immune response that creates an army of immune cells specifically designed to attack that antigen
  • highly specific to a single pathogen; can discriminate between pathogen vs. non-pathogen structures
  • highly diverse
  • becomes apparent toward the end of the prodromal phase and is maintained long after the infection clears (produces memory cells)
  • functions by producing proteins called antibodies (or immunoglobulins) which are each specific to a particular antigen
• B cells

  • cells of the immune system that make antibodies to invading pathogens
  • produced in the bone marrow, B cells migrate to the spleen and other secondary lymphoid tissues where they mature and differentiate into one of two types of cells
• plasma b cells


  white blood cells that secrete large volumes of antibodies specific to their antigen
• memory b cells 


  remember the same pathogen for faster antibody production in future infections
• T cells

  • cells of the immune system that help with the immune response
  • produced in the bone marrow and later move to the thymus where they mature into one of three types of cells
• helper t cells


  cells that express CD4 and help with the activation of cytotoxic t cells, b cells, and other immune cells by producing compounds called interleukins
• cytotoxic t cells


  cells that express CD8 and are responsible for removing pathogens and infected host cells
• T regulatory cells


  cells that express CD4 and another receptor, called CD25, that help distinguish between self and non-self molecules, and by doing so, reduce the risk of autoimmune diseases