Serratia marcescens white colony and red colony?

Question

is there such a thing as which is uv-resistant?

cos thats what my teacher ask for and we are puzzled,totally so..

or maybe he meant which is better at dna repair after uv mutation??

Answer 1

Serratia marcescens is characterized by a typical pink [not red] colony colour. This is expressed only at rather lower temperature [25 C]. Also availability of some fatty acids in the growth medium is essential. The colour is due to production of a pigment called prodigeosin. The pigment protects the cell from UV light. Non pigmented colonies are white. Hope you understand the meaning of your teacher's question now.