The domain within your query sequence starts at position 251 and ends at position 531; the E-value for the CitMHS domain shown below is 8.9e-18.

NKKKYRSHHDQMICKCLSLSISYAATIGGLTTIIGTSTSLIFLEHFNNQYPAAEVVNFGT
WFLFSFPISLIMLVVSWFWIHWLFLGCNFKETCSLSKKKKTRREELSEKRIREEYEKLGD
ISYPEMVTAFFFILMTVLWFTREPGFVPGWDSFFEKKGYRTDATVSVFLGFLLFLIPAKK
PCFGKKSDGTGQEASKGIEPIITWKDFQKTMPWEIVILVGGGYALASGSKSSGLSTWIGH
QMLSLSSLPPWAITLLACVLVSIVTEFVSNPATITIFLPIL

CitMHS

CitMHS
PFAM accession number:PF03600
Interpro abstract (IPR004680):

This domain is found in proteins belonging to the CitM transporter, NhaD Na+/H+ antiporter and Na+/sulfate symporter families, such as CitM from Bacillus subtilis [(PUBMED:11891560)], NhaD from Halomonas elongata [(PUBMED:16872527)] and SLT1 from Chlamydomonas reinhardtii [(PUBMED:20498339)].

GO process:transmembrane transport (GO:0055085)
GO component:integral component of membrane (GO:0016021)

This is a PFAM domain. For full annotation and more information, please see the PFAM entry CitMHS