(5) Microbial Metabolism and Ecology Flashcards
definition of metabolism
all chemical reaction occurring in organism or cell
mention 2 types of metabolism and their examples
- anabolism: small to large
ex. photosynthesis - catabolism: large to small
ex. glycolysis, citric acid cycle
characteristics of enzyme
reusable, highly specific, have an active site, efficient in time
energy used in metabolism
ATP
define cellular respiration
ATP production by harvesting energy from exergonic metabolism (release to surrounding)
define each of aerobic, anaerobic, and fermentation process briefly
- aerobic resp: O2 as final electron acceptor [reduction of O2 into H2O)
- anaerobic resp: inorganic compound as final electron acceptor [reduction of nitrate (NO3^-) into nitrite (NO2^-), sulfate (SO4^2-) into (H2S)]
- fermentation: only glycolysis step (no electron acceptor), produces 2 ATP molecule/ glucose
catabolism of glucose in a nutshell
- glycolysis: oxydizing glucose into pyruvate (H20, ATP, NADH)
- transition step: convert pyruvate into acetyl Co-A
& fermentation: reduce pyruvate to end product - citric acid cycle: use acetyl co-asa and release CO2 (ATP)
- electron transport system: takes electrons from NADH and FADH2 to power ATP synthesis
2 types on anabolism of carbohydrates (photosynthesis)
energy fixing and carbon fixing process
key point about energy fixing process
- electrons released from water splitting and accepted to photosystem II
- light excites some of the electrons in photosystem and pass through electron transport chain (ATP is produced as electron pass to photosystem I)
- light excites more electron and pass through another transport chain to electron acceptor NADP+, combining with protons to form NADPH
key point about carbon fixing reactions
- CO2 combine with RuBP to form unstable into 2 3PG molecules
- through ATP and NADPH from energy-fixing reactions, 2 molecules of G3P are formed
- some G3P used to make glucose and the rest goes to complex reaction involving ATP and reform RuBP
group based on ability to synthesize foods
- autotroph: synthesize their own food by simple carbon source (CO2)
- heterotroph: cannot synthesize on their own, need more complex chem compound (alcohol, glucose)
group based on source of energy
- phototroph: use light/ photon, use performed organic compound (fatty acid and alcohol) as carbon source
- chemotroph: use inorganic/ organic (glucose) for both energy and carbon source
*troph: to eat or to feed
2 types of photosynthesis
- oxygenic: use H2O, oxygen is by product, occurred in thylakoid which contain chlorophyll
- anoxygenic: use inorganic/ organic (H2S), have bacteriochlorophyll
examples of chemoheterotroph and photoheterotroph
chemo: bacteria, archaea, eukarya
photo: green and purple bacteria
examples of oxygenic and anoxygenic photosynthesis
oxygenic: cyanobacteria and algae
anoxygenic: green and purple bacteria
example reaction of oxygenic and oxygenic photosynthesis
oxygenic
- energy fixing (light reaction): electron release from H2O because light
- carbon fixing (calvin cycle): 6CO2 + 6H2O + ATP -> C6H12O6 +6O2 + ADP + P
anoxygenic
- 2H2S + CO2 -> C6H12O6 + H2O + 2S
more about chemoautotroph
- example of inorganic compound for energy source: NH3, NO2, CH4, H2S, H2
- only need CO2
- include nitrogen fixing sulfur oxidizing bacteria
define nitrogen-fixing bacteria
taking N from inorganic compound mix into organic compound (ex. amino acid)
- nitromonas convert to ammonium ions (NH4^+) into nitrite ions (NO2^-) under aerobic conditions
- Nitrobacter convert to nitrite ions (NO2^-) into nitrite ions (NO3^-) and ATP
sulfur-oxidizing bacteria in acid drainage water
acidithiobacillus thiooxidans
methanogens
Microorganisms that create methane as a byproduct of their metabolism
- anaerob (live in rich organic matter) to reduce CO2 to methane
- prokaryotic (belong to archaea and bacteria)
- reactions
CO2 + 4H2 => CH2 + 2H2O
define iron-oxidizing bacteria
gain energy by oxidization of ferrous iron
- used for industrial recovery of copper (bioleaching)
- ex. acidithiobacillus ferrooxidans
more about photoheterotroph
- produce ATP through photophosporylation, use organic compound from environment to build more compelx molecule
saprobes vs parasites in heterotroph
saprobes: feeding on dead organic matter
parasites: feedng living organic matter (human tissue)
what is microbial ecology
interactions of microorganism with biotic and abiotic component of environment
roles of microbes
producers, consumers, decomposers
why carbon cycle is important
act as blanket over planet and closely linked with flow of energy
4 steps of carbon cycle
- carbon enters atmosphere as CO2
- CO2 is absorbed by autotroph (ex. green plant)
- incorporating carbon to animal system
- animal and plant die, decompose and carbon reabsorbed by atmosphere
what is nitrogen cycle
process converting nitrogen gas (N2) to nitrogen-containing substance in soil and living organism then convert it to gas
stages of nitrogen cycle
nitrogen fixation, nitrification, assimilation, ammonification, denitrification
what is mineralization
bacteria breaks down organic matter to inorganic form of phosphorus so it’s available to plant
initial fixation of nitrogen from atmosphere is dependent on bacteria that has…
nitrogenase
why sulfur cycle is important
affect many minerals, a constituent of many protein and co factor, can be antioxidant
stages of phosphorus cycle
weathering, absorption by plant and animals, return to environment to decompose
stages of sulphur cycle
decomposition of organic compound, oxidation of H2S to elemental sulphur, oxidation of elemental sulphur, reduction of sulphates
roles of bacteria in various fields
- decomposer: soil bacteria
- nitrogen cycle: N fixing
- photosynthesis
- in food: processing, fermentation, food spoilage
- in organism: help digestion and cause disease
characteristics of archaea
- found in extreme environment: hot, salt, low pH
- source of enzyme
- interaction: protozoa and methanogenic archaea in digestive animal tracts
characteristics of protozoa
- require moist environment ( fresh and salt water, soil )
- adequate food supply
- availability of water and organic matter
roles of protozoa
- important food source for microtubules
- controlling population of bacteria, in soil they decompose it
- release nutrient to soil from bacterial digestion
roles of algae
- increase organic carbon in soil
- causing soil corrosion (from respiration product)
- prevent soil erosion, improve soil aggregation
- nitrogen fixation (by blu-green algae)
roles of fungi
- degrade organic matters
- form humus
- improve soil aggregation
- helps plants root absorb nutrient
- in food: fermentation, food spoilage
- causing disease to human, plant, and animals
examples of symbiotic and non symbiotic microbes
symbiotics: rhizobium, bradyrhizobium
non symbiotic: azospirillum, azotobacter, rhodospirillum, rhodobacter, chlorobium
nitrogen fixed symbiotically … times more than non symbiotically in free-living in bacteria
5-10 times
problem in acid mine drainage
acidification of water and surrounding soil
acidithiobacillus thiooxidans and ferrooxidans found in …
acid environment
what is microbial leaching
the process of extracting metals from ores with the use of microorganisms
microbial leaching in copper mining
using low grade copper ores
what are the physical parameter of water in bacteria
salinity, temperature, dissolved oxygen, pH
bacterial population in estuaries
pseudomonas, flavobacterium, an dvibrio
microbes in river
bacteria (bacillus, actinomyces), fungi (penicillium, aspergillus), algae (microcystis, nostoc)
meaning of color sign in water
- red: high level of chlorophyll and productivity
- yellow and green: moderate
- blue and purple: oxygen-starved area
what is phlorococcus
marine cyanobacterium that bring 50% of photosynthesis in open ocean
factors affecting microbes not found in upper regions atmosphere
humidity, temperature, oxygen content, absence of nutrient and moisture, UV radiation, pollutant, low atm pressure
role of atmosphere to microbes
as medium for dispersing microbes to new environment
