Description of the fecal microbiota of siblings from Costa Rica with and without affective and psychotic disorders

•Individuals affected of serious mental disorders have significantly increased LPS producing Pseudomonas and reduced butyrate producing Ruminococcaceae.•Bacterial taxa associated with healthy phenotype, such as Barnesiella and Rumicococcaceae were depleted in individuals affected with psychosis.•Significant alternations were found in the pathways associated with amino acid metabolism in affected individuals in comparison to the unaffected.