AST56 (sulphate transporter 2;2); sulfate transmembrane transporter. Identical to Sulfate transporter 2.2 (SULTR2;2) [Arabidopsis Thaliana] (GB:P92946;GB:O64434;GB:Q8LPG2;GB:Q8VXW4;GB:Q9SH01); similar to AST68 (Sulfate transporter 2.1) [Arabidopsis thaliana] (TAIR:AT5G10180.1); similar to putative sulfate transporter [Populus alba x Populus tremula] (GB:ABB59582.1); similar to plasma membrane sulphate transporter [Brassica oleracea var. acephala] (GB:CAM33601.1); similar to putative low affinity sulfate transporter [Brassica napus] (GB:AAZ08077.2); contains InterPro domain Sulphate transporter/antisigma-factor antagonist STAS (InterPro:IPR00