Which one of the following is NOT an example of microbial antagonism?

a. acid production by bacteria

b. bacteriocin production

c. bacteria occupying host receptors

d. bacteria causing disease

e. bacteria producing vitamin K

e. bacteria producing vitamin K

Explanation:

Microbial antagonism basically refers as microbes versus microbes i-e the indigenous microflora serve a beneficial role by preventing other microbes from becoming established in or colonizing a particular anatomic location in the body.

As all the options mentioned, refers to the microbial antagonism except option E as the normal microbes protect the host by:

1) Producing acids.

2) Bactreocin production

3) By occupying the niches that the pathogens may occupy.

But the microbes cant compete with other microbes by producing vitamins and growth factors that can be utilized by the host.

Hence option E is the right answer.