Flashcards in Bacteriology Deck (70)
What three groups of molecules are found in cytoplasm?
1.) Macromolecules - proteins (enzymes), mRNA, tRNA
2.) Small molecues - energy sources, precursors of macromolecules, metabolites or vitamins
3.) inorganic ions - such as co-factors.
what is included in the protein component of the bacterial chromosome (nucleoid)?
1.) Transcription Factors - regulate bacterial genome.
2.) Nucleoid-associated proteins (NAPs) - carry out the dynamic spatial organization of the nucleic acid.
All bacteria cytoplasmic membrane is composed of ___ & ____? What is the difference with regards to mycoplasmas?
Phospholipid bilayer and proteins. **Sterols are only present in mycoplasmas**
Where does bacterial respiration occur?
Across the cytoplasmic membrane.
What types of substances can pass a phospholipid bilayer via passive diffusion?
small lipid-soluble compounds
What is peptidoglycan and where is it found?
Peptidoglycan is a polymer of disaccharides cross-linked by short chains of amino acids (peptides). It is found in the cell envelope of bacteria.
What is unique about the cell wall of gram-positive bacteria?
Thick layer of murein (aka: peptidoglycan) and techoic acids.
What is the function of techoic acids found in the cell wall of ____ bacteria?
provides rigidity in gram positive bacteria.
What is unique about gram-negative bacteria cell envelope?
Composed of a thin layer of murein/peptidoglycan surrounded by an outer membrane.
What are the components of the outer membrane of gram-negative bacteria cell wall?
Lipopolysaccharides (LPS or endotoxins) and porins.
What are porins and where are they found?
Porins are proteins allowing diffusion of hydrophilic molecules into the periplasmic space of gram-negative bacteria. They are found in the cell envelope of gram-negative bacteria.
What is periplasmic space?
The space between the cell envelope and cytoplasmic membrane of bacteria.
What is the function of the capsule (AKA: glycocalyx) in bacteria?
Mediates attachment to particular surfaces and protects bacteria from engulfment.
Shorter and stiffer than flagella and are usually involved in adherence to surfaces.
Flagellar arrangement in which one flagella is present
Flagellar arrangement in which multiple flagella are present originating from one area of the cell wall
Flagellar arrangement in which multiple flagella are arising from multiple areas around the periphery of the cell wall.
Flagellar arrangement in which one flagella arises from each pole.
The reverse of sporulation.
What are the main genera of spore-forming bacteria?
Bacillus and Clostridium
In what group relative to oxygen requirement for growth do most clinically relevant bacteria fit in?
Facultative anaerobes - they prefer to reside in areas with oxygen but can survive in anaerobic conditions also.
An antimicrobial chemical substance that is produced by microorganisms
Define growth-promotion use of antimicrobials in animals.
When healthy animals are treated with low (sub-therapeutic) concentrations in feed to improve growth rate and efficiency of feed utilization and improve reproductive performance.
Drugs that end with -illin are ___.
Drugs that end in -cline are ___.
Drugs that end in -oxacin are __.
Quinolones (exception: oxolinic acid is also a quinolone).
Drugs that end in -enicol are ___.
Drugs that begin with cef- are ___.
What groups of drugs would be a good choice for gram-positive bacterial infections?
Penicillins, Aminopenicillins, Amoxicillin/clavulanate, Cephalosporins.