Dear Chamara,

First it is possible that Aeromonas and Shewanella grow on TCBS. 

Second morphological and biochemical identification of Vibrio is problematic because of their great metabolic variability (see Thompson et al 2004 10.1128/MMBR.68.3.403-431.2004).

Third 16S rRNA is not a reliable method to identify Vibrio but at least you can presupposes the clade.

I suggest you to do the gyrB or Hsp60 sequencing which is better and give you the species (it is easier to indentify by blast on NCBI with gyrB because there is lot of more well annotated sequences to compare to) but the gold standard still the MLSA (see Sawabe 2013).

Best Regards

Léa

Dear Girard,

Thank you very much for your kind concern and the information provided.

I hope your valuable information may guide me in the correct path.

Anyway, I have one more question that I found one partial 16S gene primer which was used to identify the genus Vibrio (Samy et al, 2014 (DOI: 10.5829/idosi.gv.2014.12.06.83316) and some primers to identify Vibrio spp. Kriem et al, 2015 (doi:10.1111/lam.12455) without sequencing.

Will it be a convenient method without doing sequencing?

Sorry for making you disturbed.

Thanks again...

Best regards,

Chamara.

Dear Chamara,

Depends on what you want to do exactly!

If you want to identify which species of Vibrio is in your samples you absolutely need to do the sequencing and gyrB will be a good choice.

If you want to know if your isolates are Vibrio or not you can use these 16S primers and see if your isolates give you the expected amplicon size. Still risky because you need to be sure 1) of the primers specificity towards Vibrio species ONLY, 2)  you had no contamination and finally this not a really common method and it can be difficult to publish such results.

Best regards,

Léa

Dear Léa,

Thank you for your valuable information and recommendations.

I realized that 16S is not a reliable method to achieve my target.

I actually need to identify the exact species of Vibrio, so I will use gyrB as you said.

Thank you once again for your assistance.

 Best regards,

Chamara

See the attached reference. It might help:

Thank you very much Dr. Jai for your kind reply.

Best regards,

Chamara.

Dear all,

I could find this reference for isolation and identification of Vibrio spp. and I could successfully use this method for isolation.

I think it is better to share it with you all.

Many thanks to the authors of this study (D. Ottaviani, L. Masini and S. Bacchiocchi, 2003).

Thank you,

Best regards,

Chamara.