Ch 5 Micro COFO

Increase in number of cells, not cell size

min andmax thresholds where cells survive (but not thrive)

Ideal (max) cell growth

Temperature, pH, osmotic pressure, light/energy

Neutralophiles- most bacteria are

Acidophiles

Alkaliphiles

Plasmolysis- cell wall is rigid but bacteria inside of cells shrinks and doesnt function properly

Extreme Halophiles or Obligate Halophiles

Faculatative halophiles

building blocks bacteria needs- C, N, S, P

structural organic molecules, energy source

in amino acids, nucleotides; most bacteria decompose protiens as source

in amino acids, thiamine, biotin; protiens decompose as source

In DNA, RNA, ATP, and membranes

Inorganic elements required in small amounts, usually used as enzyme cofactors

require O for energy metabolism; successfully detoxify reactive oxygen species (ROS); surivive only in enviroments with O

do not require O for energy metabolism; generally unable to detoxify ROS- makes O toxic, survive only in enviroments w/out O

Singlet oxygen (O2), Superoxide (O2,-), Peroxide anion (O2,-2), Hydroxyl radical (OH)

Carbohydrates, vitamins, amino acids, purines, pyrimidines

nutrients prepared for microbial growth; ex. synthetic, minimal, complex

free of microorganisms

introduction of microbes into medium

microbes growing in/on culture medium

a synthetic media in which the components are limited to only those nutrients the organism needs in order to grow

also called rich medium is nutrient-rich but less defined, often contain cell or tissue extracts

suppress unwanted microbes and encourage desired microbes; ex- McConkey Agar blocks the growth of GPC; Mannitol Salt A. blocks GNR (e. coli)

make it easy to distinguish colonies of different microbes

encourages growth of desired microbe

to seperate organisms

a population of cells arising from a single cell or spore or from a group of attached cells

contains only one species or strain

Culturing over time changes the bacteria

Lyophilization- removes all moisture

grow in a liquid culture, the resuspend in glycerol 10%; then flash-freeze, the faster the better

Lag, Log, Stationary, Death

intense activity preparing for population growth, but no increases in population; lag as genes are turned back on

logarithmic or exponential growth, increase in pop; begins dividing at particular rate; due to binary fission (bacteria) or mitosis (yeast)

period of equilibrium- no net increase. Death and production balance or no new cells are produced and death occurs

population is decreasing at log rate- long decline- could be measured in centuries

Turbidity, dry weight, detection of metabolic products (waste), consumption of nutrients or elements

Fluorescent Cytrometry- can count cell viability; fourbidine iodine only stains dead cells

Direct microscopic count- may not know viability

Matrix of (mostly) polysaccharides

dessication, antibiotics, immune system, microbicides

Quorum-sensing

On Cathers, Joint Replacements, Teeth (dental caries)