What could this organism be ?

[Thaslim.mbio]

Dear Members,

 

I just happened to come across these pink coloured colonies on some left over yoghurt and would like to know if someone can help me to identify it.

 

About the colonies.

 

I had some left over yoghurt in the fridge for a few weeks. I noticed a large number of 'Pink coloured' colonies on the surface of the yoghurt and on the sides of the container. The colonies are smooth and round and pink in colour. I have seen Serratia colonies before, but this one seems different and very interesting. I have attached a photo of the same. Could someone guess what this organism could be.

 

I would also be grateful if you could direct me to someone who would be willing to work on this organism.

 

Thanks in advance.

 

Regards,

Arif.

[Micro.Pete]

My first guess would be a Serratia spp. There are a lot of bacteria in the genus Serratia and they can differ one from another (e.g. different colony pigment). You should note that not all Serratia species produce the well known red-pink pigment. Moreover, some species that usually produce it (e.g. S. marcescens), in some condition stop producing it.

But this is of course only a guess. Further biochemical/molecular ID of the bacteria is needed.