35 terms

Microbiology - Lecture 3

Louis Pasteur
Pasteurization - kill living cell but not spores
Started to discover that disease is caused by bacteria
believed that life can arise spontaneously from nonliving materials
Francesco Redi
Proved that maggots could not arise spontaneously from decaying meat
Lazarro Spallanzani
used seed unfusions as media and showed that hermetically sealed flasks that were boiled for 1-2 hours remained sterile
Robert Koch
Described endospores, studied disease anthrax caused by Bacillus anthracis, solid media to grow microo
Koch's Postulate
Isolate disease, have it grow in media, infect healthy animal with disease, see if it causes same disease, isolate disease again and have it grow in media
Martinus Beijerinck
Enrichment culture technique is an adjustment of nutrient and culturing conditions that favor a microo of interest (selective media)
Sergei Winogradsky
Isolated first nitrogen-fixing bacterium Clostridium pasteurianum (anaerobic); shown the concept of chemolithotrophy (eat inorganic product)
Prokaryotic cell
Contains a nucleoid, where chromosomes are not separated by a membrane from cytoplasm
circular shape
rod shape
spiral shape
only found in eukaryotes; found in their membranes used for strengthening
Found in bacteria and prokaryotes; used for strengthening membranes
Ester linkage
Found in the bacterial phospholipid structure
Ether linkage
Found in the archaea phospholipid structure between the glycerol and the hydrophobic side chains
repeating units of a 5 carbon hydrocarbon; replaces fatty acids which archaea lack
archaea lipids can form when two phytanyl units come together
prevents leakage and functions as a gateway for transport of nutrients into and out of the cell
Protein anchor
site of many proteins involved in transport, bioenergetics, and chemotaxis
Energy conservation
site of generation and use of the proton motive force
is not sufficient to achieve intracellular concentrations necessary for biochemical reactions
Transport proteins
accumulate solutes against a concentration gradient and aid uptake of solutes across the cytoplasmic membrane barrier
Simple transport
involves a membrane spanning transport protein
Group translocation
a series of proteins
ABC systems
3 components
one goes in
one goes in and one goes out
both go in
cascade phosphorylization
group translocation used in the process of getting glucose into the sugar by phosphorylization from PEP
Secreted Proteins
enzyme complexes called translocases function in the secretion of proteins from the cell; include toxins and enzymes for the degradation of large polymers, which themselves cannot be imported into cells
Signal peptide
used in secreted proteins; recognize what should be exported, when recognized going to be cut off, missing the signal
Peptidoglycan is very large/thick; when stained comes out to be purple
Peptidoglycan is very small/thin; when stained will be clear, need to counterstain to appear pink
Aseptic technique
procedure that is performed under sterile conditions