Nutrition of microbes Flashcards
(36 cards)
explain microbe nutrition requirements
microorgnisms require about 10 elements in large quantities to construct carbs, proteins, lipids and nucleic acids and other elements are needed in small amounts and are part of enzymes and cofactors
what are nutrients
substances in the environment used by organisms for catabolism and anabolism
what are macronutrients
required n large amounts- e.g carbon, oxygen, hydrogen, ntrogen, sulfur and calcium
what are micronutrients
required in very small amounts- e.g iron, copper, molybdenium and zinc and these are trace elements and are essential for the activity of certain enzymes, usually as cofactors
what is also needed for growth
contaniments in water, glassware and regular growth components are adequate for growth
what are growth factors
amino acids= protein synthesis
purines and pyrimidines= nucleic acid synthesis
vitamins= forming part enzyme cofactors and only very small amounts are needed for growth
heterptrophs
CHO- organic carbon
autotrophs
CO2
Microorganisms have extraordinary….
flexability
omnivores
use over 100 carbon compounds
fastidious
catabolise only a few carbon compounds
phototrophs
use light as an energy source
chemothrophs
obtain energy from oxidation of chemical compounds
lithotrophs
use reduced inorganic substances as their electron source- energy
organotrophs
extract electrons from organic compounds
photoautotrophs
use light energy, inorganic hydrogen and CO2 carbon source as sources of energy and found in algae and purple and green bacteria
photoheterotrophs
uses light energy and organic carbon source and sources of energy and found in green sulfur bacteria and purple nonsulfur bacteria
chemoautotrophs
chemical energy source and CO2 carbon source as sources of energy and found in sulfur-oxidising bacteria and hydrogen bacteria
chemoheterotrophs
chemcial energy source and organic carbon source as sources of energy and found in most bacteria, fungi and protozoa
what can nutrients frequently not pass
the selectively permeable plasma membrane through passive diffusion
what are nutrients carried through (the mechanisms)
passive transport (simple difusion), facilitated difusion, active transport and group translocation
what is passive diffusion
molecules move from a region of higher concentraiton to one of lower concentration due to thermal agitation-no energy used and no carieer protein used
what is facilitated diffusion
difusion process is aided by a carier and involves careier proteins, permeases and higher con to a lower con
no energy input
what are permeases
they are embedded in the plasma membrane and are carier proteins that increases the rate of diffusion across selectively permeabke membranes
