Identify the catabolic pathways used by the following bacteria:

Pseudomonas Oxidizes glucose
Lactobacillus Ferments glucose
Alcaligenes Neither oxidizes nor ferments glucose
Escherichia Oxidizes and ferments glucose

The different catabolic processes followed in this case are as follows : -

Pseudomonas  :- Glycolysis, Krebs cycle, electron transport chain
Lactobacillus   :- Glycolysis, fermentation
Alcaligenes       :-Hydrolyzes proteins, oxidized amino acids in Krebs cycle
Escherichia       :-Glycolysis, Krebs cycle, ETC or glycolysis, fermentation


GLYCOLYSIS :- Glycolysis is the catabolic pathway which converts glucose C6H12O6, into pyruvate, CH3COCOO− + H+. The free energy released in this process is used to form the high-energy compounds ATP (adenosine triphosphate) and NADH (reduced nicotinamide adenine dinucleotide).

KREBS CYCLE :- The citric acid cycle or tricarboxylic acid cycle (TCA cycle), or the Krebs cycle is a series of chemical reactions used to generate energy through the oxidization of acetate derived from the glycolysis into carbon dioxide. In addition, the cycle provides precursors including certain amino acids as well as the reducing agent NADH that is used in numerous biochemical reactions.

ELECTRON TRANSPORT CHAIN :- An electron transport chain (ETC) couples electron transfer between an electron donor (such as NADH) and an electron acceptor (such as O2) with the transfer of H+ ions (protons) across a membrane. The resulting electrochemical proton gradient helps to generate chemical energy in the form of adenosine triphosphate (ATP).

FERMENTATION :- Fermentation is a metabolic process which converts sugar to acids, gases and alcohol. Here there is absence of the electron transport chain and use of  a reduced carbon source, such as glucose takes place for making products like lactic acid or acetate. only substrate level phosphorylation is used that yields a much lower amount of ATP. here the electron donor and electron acceptor are both an ORGANIC COMPOUND .

PROTEIN HYDROLYSIS :-

Protein hydrolysis is the process by which peptide bonds are broken under acidic conditions at high temperatures, generating free amino acid residues. These amino acids in their oxidized states are used to generate different intermediates of the krebs cycle and there by generating reducing equivalents such as NADH and FADH that helps in the oxidative phosphorylation .