Kpkt killer toxin: a promising option for the manage-ment of microbial contaminations in the wine and food industry

abstract

English

Yeast killer toxins are naturally secreted glycoproteins that kill microorganisms of agrifood interest and microbial pat-hogens through a toxin-receptor-mediated mechanism. Among yeast killer toxins, the one produced by Tetrapi-sispora phaffii, named Kpkt, is a 33 kDa β-glucanase that, being active on Kloeckera/Hanseniaspora, Saccharomyco-des and Zygosaccharomyces yeast, may find application in the management of microbial contamination in grape must and sweet beverages. However, as for other killer toxins, the industrial exploitation of Kpkt has been often proposed, but never realized. This is possibly due, among the others, to the lack of studies regarding their effect on the consumers, and to their limited production by the native producers. Considering that the utilization of recombinant enzymes is admitted by the food industry, KpKt coding gene was expressed in Pichia pastoris and the spectrum of action of the recombinant toxin was thoroughly evaluated on microbial targets and non-target eukaryotic models. Heterologous expression resulted in a 50-fold increase in the production of Kpkt. This was active on a rich portfolio of food-related yeast and bacteria and proved harmless on human keratinocytes HaCaT cells thus appearing a promising option for the management of microbial contamination in the wine and food industry

killer toxin, natural antimicrobials, β-glucanase

MÁROVÁ, I.

1. 2. 2023

Sciendo

Italy

2564-615X

The Eurobiotech Journal

1

7

2564-615X

The EuroBiotech Journal

7

1

Republic of Italy

27

27

1

https://sciendo.com/article/10.2478/ebtj-2023-0003