Heterologous expression of a Glyoxalase I gene from sugarcane confers tolerance to several environmental stresses in bacteria.

Glyoxalase I belongs to the glyoxalase system that detoxifies methylglyoxal (MG), a cytotoxic by-product produced mainly from triose phosphates. The concentration of MG increases rapidly under stress conditions. In this study, a novel glyoxalase I gene, designated as was identified from sugarcane. had a size of 1,091 bp with one open reading frame (ORF) of 885 bp encoding a protein of 294 amino acids. SoGloI was predicted as a Ni-dependent GLOI protein with two typical glyoxalase domains at positions 28-149 and 159-283, respectively. was cloned into an expression plasmid vector, and the Trx-His-S-tag SoGloI protein produced in was about 51 kDa. The recombinant cells expressing compared to the control grew faster and tolerated higher concentrations of NaCl, CuCl, CdCl, or ZnSO. ubiquitously expressed in various sugarcane tissues. The expression was up-regulated under the treatments of NaCl, CuCl, CdCl, ZnSO and abscisic acid (ABA), or under simulated biotic stress conditions upon exposure to salicylic acid (SA) and methyl jasmonate (MeJA). SoGloI activity steadily increased when sugarcane was subjected to NaCl, CuCl, CdCl, or ZnSO treatments. Sub-cellular observations indicated that the SoGloI protein was located in both cytosol and nucleus. These results suggest that the gene may play an important role in sugarcane's response to various biotic and abiotic stresses.