You decide to go on vacation in the mountains, where you are staying in a cabin. Unfortunately, when you turn on the water in the cabin you smell hydrogen sulfide (H2S) gas. After some research, you find out that the H2S may be due to the presence of sulfur bacteria living in your pipes. What molecule do these bacteria use as an electron acceptor?

Answer: Bacteria will use the oxidised form of sulphur. Among all the forms of sulphur molecule such as sulphate which is the more oxidised form and also the other forms like thiosulphate, elemental sulphur, sulphite, hyposulphite can be used as an electron acceptor. As the coupling of these organic compounds occur, these sulfur bacterias obtain energy from the subsequent oxidation and then reduction of sulfur forms from sulphate to sulphide which is then released in the environment.