Catalyzes the reversible hydration of cis-homoaconitate to (2R,3S)-homoisocitrate, a step in the alpha-aminoadipate pathway for lysine biosynthesis. (2R,3S)-homoisocitrate = cis-homoaconitate + H2O Binds 1 [4Fe-4S] cluster per subunit. Amino-acid biosynthesis; L-lysine biosynthesis via AAA pathway; L-alpha-aminoadipate from 2-oxoglutarate: step 3/5. Belongs to the aconitase/IPM isomerase family.