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In the reverse direction the enzyme catalyses the regioselective carboxylation of phenol into salicylate.
References
Kirimura K, Gunji H, Wakayama R, Hattori T, Ishii Y (April 2010). "Enzymatic Kolbe-Schmitt reaction to form salicylic acid from phenol: enzymatic characterization and gene identification of a novel enzyme, Trichosporon moniliiforme salicylic acid decarboxylase". Biochemical and Biophysical Research Communications. 394 (2): 279–84. doi:10.1016/j.bbrc.2010.02.154. PMID20188702.