Discovery of Two 17β-Estradiol Metabolic Microbes and Their Metabolic Enzyme from Cecal Contents of Hy-Line Brown Laying Hens

Abstract

17β-Estradiol (E2), a reproductive hormone closely associated with the decline in egg production of laying hens, has attracted considerable attention. Although microbial feed additives have significantly alleviated this decline, the direct interactions between the host microbe and E2 remain poorly understood. In the present study, two E2-metabolic strains (Brevibacillus borstelensis NRRL NRS-818 and Acinetobacter radioresistans) were isolated through gradient pressure acclimatization with E2. Further RNA-Seq analysis of these two strains grown in medium with or without E2 identified 14 upregulated genes that are likely involved in E2 degradation. Subsequently, 3-hydroxyacyl-CoA dehydrogenase/enoyl-CoA hydratase family protein and bifunctional precorrin-2 dehydrogenase/sirohydrochlorin ferrochelatase from Brevibacillus borstelensis NRRL NRS-818, as well as enoyl-CoA hydratase/isomerase family protein from Acinetobacter radioresistans DSM 6976, were identified as E2-metabolic enzymes via the construction of an Escherichia coli strain. In summary, we successfully identified E2-metabolic strains with predictive value for changes in egg production of laying hens.