Sulfate-reducing
bacteria (SRB), such as
Desulfobacter
postgatei
are found in oil wells. However, they lead
to the release of hydrogen sulfide. This in turn leads to the iron
sulfide scale formation (pyrite). ATP sulfurylase is an enzyme present
in SRB, which catalyzes the formation of adenylyl sulfate (APS) and
inorganic pyrophosphatase (PPi) from ATP and sulfate. This reaction
is the first among many in hydrogen sulfide production by
D. postgatei
.
Consensus scoring
using molecular docking and machine learning was used to identify
three potential inhibitors of ATP sulfurylase from a database of about
40 million compounds. These selected hits ((
S
,
E
)-1-(4-methoxyphenyl)-3-(9-((
m
-tolylimino)methyl)-9,10-dihydroanthracen-9-yl)pyrrolidine-2,5-dione;
methyl 2-[[(1
S
)-5-cyano-2-imino-1-(4-phenylthiazol-2-yl)-3-azaspiro[5.5]undec-4-en-4-yl]sulfanyl]acetate;
and (4
S
)-4-(3-chloro-4-hydroxy-phenyl)-1-(6-hydroxypyridazin-3-yl)-3-methyl-4,5-dihydropyrazolo[3,4-b]pyridin-6-ol),
known as A, B, and C, respectively) all had good binding affinities
with ATP sulfurylase and were further analyzed for their toxicological
properties. Compound A had the highest docking score. However, based
on the physicochemical and toxicological properties, only compound
C was predicted to be both safe and effective as a potential inhibitor
of ATP sulfurylase, hence the preferred choice. The molecular interactions
of compound C revealed favorable interactions with the following residues:
LEU213, ASP308, ARG307, TRP347, LEU224, GLN212, MET211, and HIS309.