Adsorption of Tolaasins, the Toxins Behind Mushroom Bacterial Blotch, by Microbacterium spp. is Insufficient for Its Detoxification

• Published in: Current microbiology Vol. 77; no. 6; pp. 910 - 917
• Main Authors: Tomita, Shun, Hirayasu, Anna, Kajikawa, Akinobu, Igimi, Shizunobu, Shinohara, Hirosuke, Yokota, Kenji
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.06.2020; Springer Nature B.V
• Subjects: Adsorption; Agaricus - drug effects; Bacteria; Bacterial Proteins - chemistry; Bacterial Proteins - toxicity; Bacterial Toxins - chemistry; Bacterial Toxins - toxicity; Biodegradation; Biological activity; Biological control; Biological Control Agents - chemistry; Biomedical and Life Sciences; Biotechnology; Blotch; Depsipeptides - chemistry; Depsipeptides - toxicity; Detoxification; Life Sciences; Lipodepsipeptides; Liquid phases; Microbacterium - classification; Microbacterium - physiology; Microbiology; Mushrooms; Solanum tuberosum - drug effects; Solanum tuberosum - microbiology; Strains (organisms); Toxins
• ISSN: 0343-8651; 1432-0991
• DOI: 10.1007/s00284-020-01884-w

Tolaasins are lipodepsipeptides secreted by Pseudomonas tolaasii , the causal agent of bacterial blotch on several kinds of cultivated mushrooms. Our previous study reported on tolaasin detoxification by Microbacterium sp. K3-5 as a potential biocontrol of the disease. In this study, the tolaasin-detoxifying activities of various type strains of Microbacterium spp. were evaluated through chemical and biological assays. The bacterial cells of all tested strains of Microbacterium spp. showed tolaasin I-elimination from liquid phase. However, the toxin activities of tolaasins were still retained on the tolaasin-treated bacterial cells of all Microbacterium strains except M. foliorum NBRC 103072 T . Furthermore, intact tolaasin I was recovered from the tolaasin-treated bacterial cells of all tested strains except M. foliorum NBRC 103072 T . Our data reveal that Microbacterium spp. can be characterized as effective tolaasin I-eliminating bacteria through cell adsorption, but that this adsorption alone is insufficient for actual tolaasin detoxification. The biological degradation process must be needed to carry out the detoxification.