prokaryotes- beneficial effects Flashcards
what is bioremediation?
any process which uses microorganisms or their enzymes to return the environment to its original condition after contamination.
many substances have been used in the environment that were once thought to be harmless that have since been found to have a dangerous bio-accumulative affect on plants and animals.
examples of bioremediation
bioremediation of DDT using Sphingobacterium species
Alcanivorax Borkumensis in the bioremediation of an oil spill
Pseudomonas Veroni in the bioremediation of heavy metals.
what is bioleaching?
extraction of specific metals from their ores using bacteria
example of bioleaching
extraction of copper using Thiobacillus bacteria
what is fermentation?
a type of anaerobic respiration where oxygen is not used as the terminal electron acceptor
fermentation in the food industry results in the formation of a variety of useful products.
example of fermentation
production of cheese by the breakdown of lactose into lactic acid by lactobacillus, lactococcus, or streptococcus families.
example of genetic engineering
the gene for human growth hormone or insulin can be copied using PCR and inserted into the bacterial plasmid. The recombinant bacteria can then produce human growth hormone or insulin for use in medical therapy
example of microbial antagonism
in the human vagina, lactobacillus species maintains a pH of 3.5-4.5 which inhibits the growth of candida albicans as they cannot grow in acid conditions
the use of antibiotics can cause the pH to become neutral allowing for the growth of candida albicans which cause thrush.
example of beneficial bacteria in the human body
bacteroides fragilis, bacteroides vulgatus, and E.coli produce vitamin K which is essential for blood clotting in humans.
bacteria in the nitrogen cycle
nitrification
> nitrosomnas - oxidises ammonium to nitrite
> nitrobacter - oxidises nitrite to nitrate
denitrification > reduction of nitrate to nitrogen by bacillus, Pseudomonas, Spirillum, Thiobacillus.
bacteria in the carbon cycle
algae (cyanobacteria) and green & purple sulphur bacteria fix/incorporate CO2 into organic matter using energy from sunlight
Thiobacillus and Beggiatoa also fix CO2 into organic matter
bacteria in the sulphur cycle
thiobacillus are motile, Gram-negative rods found in mud,sewage, bogs, mining drainage, and brackish springs. Thiobacillus oxidise elemental sulphur, sulphides, and thiosulphate, into sulphates which can be taken up by plants
bacteria in the epilimnion
in water, oxygenic photosynthesis by cyanobacteria in the epilimnion generates O2 and minerals for aquatic life
bacteria in the hypolimnion
in the hypolimnion, anoxygenis photocynthesis by purple & green sulphur bacteria generates biomass in oxygen depleted environments - this biomass can be used as nutrients for other organisms.
anaerobic decomposers breakdown dead and decaying matter contributing to nutrient cycling and redistribution of these nutrients during the autumn overturn.
