Question

Write comprehensive notes on the following:

a) Purple non-sulphur bacteria
b) Pseudomonads
c) Biochemical pathway for the production of acetic acid by
Acetobacter aceti
d) IMViC reactions in identifying Enterobactericeae
e) Purple sulpher bacteria
f) Cynobacteria
g) Pseudomonas aeruginosa

Answer 1

a) Purple non-sulphur bacteria: these are photosynthetic bacteria which have the capability of producing their food through the process of photosynthesis. These are referred to as proteobacteria. These have pigments of bacteriochlorophyll or a, which are referred to as carotenoids resulting in colours in a wide range such as red, purple, brown as well as orange. These bacteria are microaerophilic or anaerobic and are generally found in environments that include hot springs or stagnant bodies of water, as well as the bats of microbes found in intertidal zone. These bacteria do not produce oxygen rather they use sulfide in forms of thiosulphate or sulphide as the donor of electron in the photosynthetic pathway. Sulfur Gets oxidised so that elemental sulfur granules could be produced.
b) Pseudomonads: these are a family of bacteria that are gram negative and show great diversity. These are present in various environments and are opportunistic pathogens. These bacteria are rod shaped and are non-spore forming along with being catalase positive as well as oxidase positive. They secrete a fluorescent siderophore in the Ron limiting conditions. Give a positive result to the oxidase test and Indol negative and citrate positive
c) Biochemical pathway for the production of acetic acid by Acetobacter aceti: This method is also referred to as bio production of acetic acid. It said is used in various platforms for being a food preservative. Production synthetically was done using ethylene or methanol and biological ways are being looked into. These bacteria regenerate NAD + and carry out recycling of the acetyl co a resulting in acetogenexis such that acetate is released in the environment. AceTogenesis occurs when carbon fluctuations in cells exceed their capacity.
d) IMViC reactions in identifying Enterobactericeae: there are four definitely test in this reaction which include indole production, methyl red test, the VP test and citrate utilisation test. Most of the bacteria are similar in their cultural characteristics as well as morphological characteristics as a result of which these biochemical tests are performed.