The human gut microbiota (HGM) colonizing
human gastrointestinal
tract (HGT) confers a repertoire of dynamic and unique metabolic capacities
that are not possessed by the host and therefore is tentatively perceived
as an alternative metabolic ″organ″ besides the liver
in the host. Nevertheless, the significant contribution of HGM to
the overall human metabolism is often overlooked in the modern drug
discovery pipeline. Hence, a systematic evaluation of HGM-mediated
drug metabolism is gradually important, and its computational prediction
becomes increasingly necessary. In this work, a new data set containing
both the HGM-mediated metabolism susceptible (HGMMS) and insusceptible
(HGMMI) compounds (329 vs 320) was manually curated. Based on this
data set, the first machine learning (ML) model, a new structural
alerts (SA) model, and the K-nearest neighboring dietary compounds-based
average similarity (AS) model were proposed to directly predict the
HGM-mediated metabolism susceptibility for small molecules, and exhibit
promising performance on three independent test sets. Finally, consensus
prediction (ML/SA/AS) for DrugBank molecules revealed an intriguing
phenomenon that a typical Michael acceptor ″α,β-unsaturated
carbonyl group″ is a very common warhead for the design of
covalent inhibitors and inclined to be metabolized by HGM in anaerobic
HGT to generate the reduced metabolite without the reactive warhead,
which could be a new concern to medicinal chemists. To the best of
our knowledge, we gleaned the
first HGMMS/HGMMI data set, developed the first HGMMS/HGMMI classification
model, implemented a relatively comprehensive program based on ML/SA/AS
approaches, and found a new phenomenon on the HGM-mediated deactivation
of an extensively used warhead for covalent inhibitors.