Question

Microbiology

What type of metabolic interaction among microorganisms occurs in the rumen and what two types of prokaryotes are involved? How is each affected by these interactions?

Answer 1

Ans: Microbes found in the rumen of ruminants utilize host feed material as their substrate for growth.

For example, Ruminococcus bacteria survive in cow's gut by breaking down cellulose (a complex carbohydrate obtained from grass) into monosaccharide which could be used for cow's growth and also, assists in bacteria survival by providing it nutrients.

However, all microorganisms that live in the gut can't breakdown cellulose and use it directly for energy metabolism. Metabolic interaction occurs in the rumen as most of the hydrolytic enzymes are extracellular in nature and thus, some monosaccharides are also secreted in the rumen fluid along with the enzyme. These secreted monosaccharides are used as growth substrates by other microbial species that live in the gut.

Also, waste products generated by the metabolism of 1 bacteria are also utilized as a substrate by other bacteria.

For example, CO2 and H2 produced as a waste product by the metabolism of other bacteria are used by methanogens (Methanobacterium ruminantium) as a substrate.