Discovery of a Bacterial Gene Cluster for Deglycosylation of Toxic Potato Steroidal Glycoalkaloids α-Chaconine and α-Solanine

Abstract

Potato juice is a byproduct of starch processing currently used as feed. However, potato proteins are an untapped source of high-protein food for human nutrition if harmful constituents notably glycoalkaloids (GAs) are detoxified. The two principle GAs found in potato are α-chaconine and α-solanine, both consisting of a solanidine aglycone with a carbohydrate side chain. The first step in the detoxification of these compounds is the removal of the trisaccharide. Whole-genome sequencing of a bacterial isolate, Arthrobacter sp. S41, capable of completely degrading α-chaconine and α-solanine, revealed the presence of a gene cluster possibly involved in the deglycosylation of GAs. Functional characterization confirmed the enzymatic activity of the gene cluster involved in the complete deglycosylation of both α-chaconine and α-solanine. The novel enzymes described here may find value in the bioconversion of feed proteins to food proteins suitable for human nutrition.

The Combination of Lead and Bacillus coagulans R11 Increased the Concentration of Alpha-Solanine in the Cecum of Laying Hens and the Pathogens Abundance Decreased

“…Hennessy found that Arthrobacter sp. S41 could degrade α-solanine due to a novel enzyme (Hennessy et al, 2020), but in the present study, the concentration of α-solanine increased in only the B. coagulans R11-fed groups and tended to decrease in the Pb group compared with the Blank group. Thus, we concluded that B. coagulans R11 could stimulate α-solanine production rather than inhibit bacterial growth, especially in the condition of lead tolerance.…”

Microbial Deglycosylation of Plant Metabolites: A Case Study with Actinoplanes missouriensis 431T

“…Previously, an α- l -rhamnosidase from the actinobacteria Arthrobacter sp. S41 was reported as part of the gene cluster involved in the first step of potato glycoalkaloid detoxification . Here, five genes were related to the first steps of flavanone catabolism.…”

“…S41 was reported as part of the gene cluster involved in the first step of potato glycoalkaloid detoxification. 50 Here, five genes were related to the first steps of flavanone catabolism. Considering the cellular location of both enzymes and the substrate specificities, we propose a catabolic pathway for the hydrolysis of hesperidin and the subsequent generation of monosaccharides (Table 2).…”

Liquid Chromatography Mass Spectrometry Quantification of α-solanine, α-chaconine, and Solanidine in Potato Protein Isolates

“…Furthermore, it has been shown that 5% of α-chaconine and α-solanine were hydrolyzed to other intermediate structures during a 3 h simulated in vitro digestion [25]. A recent study also discovered a bacterial gene cluster involved in deglycosylations of α-chaconine and α-solanine and thereby potentially detoxification of the potato GAs [35].…”