Pseudomonas sp. UW4 acdS gene promotes primordium initiation and fruiting body development of Agaricus bisporus

AbstractTo simplify industrial mushroom cultivation, we introduced a bacterialPseudomonas sp. UW4acdS gene, encoding 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase (AcdS), into fungusAgaricus bisporus. TransformantA. bisporus-acdS14 cased with sterilized-vermiculite generated primordia 5  days sooner than wild-type strain, confirming the specific role of the AcdS enzyme. Being consistent with the AcdS enzyme activity increased by 84%, the mycelium growth rate was increased by 25%; but, the ACC and ethylene concentrations were reduced by 71% and 36%, respectively, in theA. bisporus-acdS14 transformant. And the bacteriumP. sp. UW4 attachment on the mycelium of theA. bisporus-acdS14 transformant was drastically reduced. We conclude that the heterogeneously expressed bacterialacdS gene degrades ACC and reduces ethylene-synthesis, eliminating ethylene inhibition on the mycelium growth and primordium formation inA. bisporus. Our results provide new insights into the mechanism underlying casing soil bacterium, and help formulate a casing-less cultivation for the next-generation mushroom industry.
Source: World Journal of Microbiology and Biotechnology - Category: Microbiology Source Type: research