bacterial metabolism Flashcards
energy source for phototrophs
light
energy source for chemotrophs
oxidation of inorganic compounds
electron sources for lithotrophs
reduced inorganic molecules
electron sources for organotrophs
organic molecules
carbon sources for autotrophs
CO2 sole or principal biosynthetic carbon source
carbon source for heterotrophs
reduced, preformed, organic molecules from other organisms
for heterotrophs organic carbon is the
carbon source
- pyrivayte generated as a key molecule through glycolysis. If oxygen is present pyruvate can be oxidised to carbon dioxide. Oxidation is the removal of electrons. these electrons then enter the ETC where the majority of ATP is produced
the calvin cycle allows the
further oxidation of pyruvate and the generation of further electrons
denitrification in E.coli used
the enzyme nitrate reductase
chemolithotrophy
oxidation of inorganic materials- most are autotrophs
e.g. inorganic energy and electron source goes the ETC and ATP is produced
nitrifying bacteria
able to grow chemolithotrophicaly at the expense of reduced inorganic nitrogen compounds. Found in alpha, beta, gimme and delta proteobacteria
fermentation
if there is not ETC or terminal electron acceptor, the reduced NADH needs to be oxidised back to NAD+ for glycolysis. Pyruvate reduced by NADH
–> substrate level phosophorylation
3 parts of the nitrogen cycle
1) nitrogen fixation
2) nitrification
3) denitrification
how much of air is nitrogen
78%- key for amino and nucleic acids and important part of ATP
nitrogen fixation
anaerobic process in which N2 is reduced to NH3. Bacteria are responsible for this process. Plants cannot use nitrogen in our atmosphere without nitrogen fixing bacteria.
