Environmental microbiotechnology

Question 1

what are organohalogens

Answer 1

class of organic compounds that contain at least one halogen (fluorine [F], chlorine [Cl], bromine [Br], or iodine [I]) bonded to carbon.

Question 2

what are DTDs

Answer 2

pesticides - bad

Question 3

what are PCBs

Answer 3

industrial products/chemicals - bad

Question 4

an example of a bed chemical in water that is removed

Answer 4

phenols

Question 5

what else is removed from water in waste water treatment

Answer 5

remove high BOD compounds - biological oxygen demand - measures the amount of organic carbons that bacteria can oxidise

Question 6

what is nitrification

Answer 6

oxidation of ammonia to nitrite, then nitrite to nitrate

Question 7

what is denitrification

Answer 7

organic matter is oxidised to produce nitrogen gas - harmless to the atmosphere
nitrate reduced to nitrogen

Question 8

what is the Anammox process

Answer 8

nitrification and denitrification where you start with ammonia and end with nitrogen (giving out water)
nitrite can be used to oxidise ammonium - you don’t need oxygen - use the intermediate

Question 9

what is kuenenia stuttgartiensis

Answer 9

a bacterium that contains an anammoxosome

Question 10

what happens in the anammoxosome

Answer 10

anaerobic oxidation of nitrite

Question 11

what are the advantages of the anammox process

Answer 11

don’t need oxygen
88% less co2 produced
90% reduction in operation costs

Question 12

what are xenobiotics

Answer 12

synthetic compounds with no obvious counterparts in the natural world - we make them - foreign - introduced

Question 13

3 examples of xenobiotics

Answer 13

pesticides, fertilisers, PAHs - from combustion processes

Question 14

what is biomagnification

Answer 14

when a substance accumulates in the fats of larger animals as it moves through the food chain eg DDD in ducks from the water x1000 conc

Question 15

why is a mixture of microos better at degrading organic compounds rather than a pure culture

Answer 15

all have different degradation properties
one could partially degrade, then another could take over
some might be more sensitive than others

Question 16

many xenobiotics are mixed with heavy metals, what does this mean for the degradation

Answer 16

slows down the degradation process as gram +ive and -ive are sensitive to toxic metals

Question 17

what is bioremediation

Answer 17

organisms used to eliminate environmental contamination eg. oil spills

Question 18

what does in situ mean

Answer 18

relies on microorganisms indigenous to the site of contamination - organisms are natural - found there anyay

Question 19

what are common limiting factors to the microorganisms doing the degrading

Answer 19

nitrogen, phosphorus, oxygen - fertilisers added to encourage degradation

Question 20

what is Ab

Answer 20

a bacterium that preferably uses alkane hydrocarbons as substrates - likes exclusively on alkanes

Question 21

name the alkanes

Answer 21

methane
ethane
propane
butane

Question 22

what are pseudomonas

Answer 22

gram -ive bacteria

abundant in soil, very metabolically versatile, inc. hydrocarbons

Question 23

what do pseudomonas contain

Answer 23

a catabolic plasmid that is self transmissable

Question 24

what is the benzine ring

Answer 24

a major building block in nature, found in lignin

Question 25

what are AHs and an example

Answer 25

Aromatic Hydrocarbons eg benzene

Question 26

what are AH’s degraded to

Answer 26

catechol

Question 27

what are the two pathways that can be induced depending on different benzene and catechol derivatives and where do the products feed into

Answer 27

ortho-cleavage pathway - Acetyl CoA + succinate
meta-cleavage pathway - Acetaldehyde + pyruvic acid
feed into central metabolism - TCA cycle (Krebs cycle)

Question 28

where would anaerobic degradation have to occur

Answer 28

in waterlogged places/ rubbish tips

Question 29

what is toluene and how is it degraded

Answer 29

an aromatic hydrocarbon

oxidised to Co2 using iron as the e- acceptor

Question 30

what technique is used to recover metals from their ore

Answer 30

bioleaching - solubilisation by acid production

Question 31

what technique is used for recovery of precious metals

Answer 31

bioaccumulation - microos accumulate them due to -ive surface charge