Does Bacillus velezensis Strain RP137 from the Persian Gulf Really Produce an Aminoglycoside?

Abstract

It has recently been published that an aminoglycoside, S‑137‑R, is produced by a newly isolated Bacillus velezensis strain RP137 from the Persian Gulf (Pournejati et al. in Curr Microbiol 76:1028-1037, 2019). However, the analytical data presented by the authors do not allow for a structure elucidation. The data does not even prove that the authors studied an individual compound in terms of analytics and biological activity. The purity of the substance S-137-R is severely doubted because the analytics is inadequate. The molecular mass cannot be assigned on the basis of the published mass spectrum. Fundamental 2D experiments as well as proper data analysis of the presented 1D data are missing. There is no adequate comparison with other data of structurally characterized and confirmed aminoglycosides possible. In conclusion, an assignment of an aminoglycoside is scientifically not justified. Consequently, the EFSA's QPS listing requirement to prove the "absence of aminoglycoside production ability" should be no obligation anymore to approve a B. velezensis species as probiotic.