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Newbies!

[Phan]

I has a peptide with MW 850, and based on its chemical shifts (DMSO), it was identified as anabaenopeptin DA850 (DMSO) (which is similar to the aeruginosin DA850 as shown in below Figure). I would like to try to use this tool, upon key in the HSQC data (DMSO), the results are as shown in below Figure. The cosine score of the expected compound was not on the top list, could it be the (Calcd CDCl3)? What should I do?

[Kyo Bin Kang]

Basically this kind of in silico data interpretation tools (especially regarding GNPS for MS/MS) provides an initial direction for data interpretation, but those are not a magic box which always gives you an 100% correct answers.

You still need a manual inspection on the spectrum to confirm the identification. If it gave you an identification of anabaenopeptin DA850, then it means it's the true structure and SMART has some points to be improved for detecting subtle structural differences. :)

2020년 3월 2일 월요일 오후 1시 3분 57초 UTC+9, Phan 님의 말:

[beowu...@gmail.com]

Thank you for raising your concerns, Phan. I also would like to thank Kyobin here for sharing his opinion and advice. 

For Phan, could you please double check the proton correlations in your COSY, TOSCY or HMBC spectra to rule out the other possibilities? The HSQC spectra of anabaenopeptin MM850 and Aeruginosin DA850 must look very much alike in the same solvent.

Chen