week 4 Flashcards
what elements are essential for all microorganisms
H, C, N, O, P, S
what is the cell mostly made out of ?
proteins (55%)
RNA (20.5%)
macronutrient
required in large amounts and play key roles in cell structure and metabolism
C, H, and O
micronutrient
present in much smaller amounts and are involved in enzyme function and maintenance of protein structure
- manganese, zinc, and nickel
List of growth factors
PABA
folic acid
Biotin
B12
B1
B6
Nicotinic acid
riboflavin
pantothenic acid
lipoic acid
vitamin k
coenzymes M and B
F420 and F430
minimum temperature
transport processes so slow that growth cannot occur
maximum temperature
protein denaturation
collpase of the cytoplasmic membrane
thermal lysis
psychrophile
optimal growth in cold tempertaures
mesophile
optimal growth around (36-39)
thermophile
optimal growth around 60
hyperthermophile
live in very hot environments
Use Ca2+ to help stabilize proteins and are adapted to high temps
osmolarity
the total concentration of a solute
halophiles
- live in high solute environments
- have things inside cell that aren’t membrane permeable so they contribute to osmolarity of the cell so water does not rush out
Obligate aerobe
O2 is required
aerobic respiration
Facultative anaerobe
not required, but grows better with O2
aerobic respiration, anaerobic resp., fermentation
Microaerophilic
required but at levels lower than atmospheric
aerobic respiration
aerotolerant
not required and grow no better with O2 present
fermentation
obligate anaerobe
O2 is harmful or lethal
fermentation or anaerobic respiration
what does oxygen produce?
superoxide
hydrogen peroxide
hydroxyl radical
what do aerobes produce
superoxide dimutase
catalase
peroxidase
barophilic
require pressure because they have adapted membranes
what does optical density measure?
live and dead cells and everything else in the sample
what does membrane filtration measure?
measures alive bacteria
bacteriostatic
prevents growth but does not kill or lyse
bactericidal
dead but not lysed (remains intact)
bacteriolytic
cells die and they are lysed (irreversible)
decimal reduction time
time it takes to kill 90% of bacteria
sterilization
destruction or removal of all viable organisms
- inc. endospores!!
disinfection
killing, inhibition, or removal of disease causing organisms but not endospores
sanitization
reduction of microbial population to levels deemed safe
antisepsis
prevention of infection of living tissue by microorganisms
- kill or inhibit growth when applied to surface of tissue
chemotherapy
kill or inhibit internal microorganisms
physical methods to kill bacteria
high moist heat
- even kills endospores
low moist heat
- kills pathogens present but does not sterilize
UV radiation
Gamma radiation
mechanical methods to kill bacteria
membrane filtration
phenolics
act by denaturing proteins and disrupting cell membranes
does not kill spores but kills other bacteria
alcohols
bactericidal, fungicidal but does not kill spores
denatures proteins
Halogens
kills bacteria, fungi, viruses
may kill spores at high concentrations
aldehydes
crosslink proteins
stops metabolic activity
kills most bacteria, fungi, and spores
Quaternary ammonium compounds
detergents that have antimicrobial activity
kill most bacteria BUT not endospores
Hydrogen peroxide
kills most bacteria, viruses, and fungi
