This family consists of several bacterial ThuA-like proteins. ThuA appears to be involved in utilisation of trehalose [1]. The thuA and thuB genes form part of the trehalose/sucrose transport operon thuEFGKAB, which is located on the pSymB megaplasmid. The thuA and thuB genes are induced in vitro by trehalose but not by sucrose and the extent of its induction depends on the concentration of trehalose available in the medium [2]. ThuA is involved in the conversion of of disaccharides to their respective 3-keto derivatives [3].

1: Redundancy in periplasmic binding protein-dependent transport systems for trehalose, sucrose, and maltose in Sinorhizobium meliloti. Jensen JB, Peters NK, Bhuvaneswari TV; J Bacteriol. 2002;184:2978-2986. PMID:12003938

2: Lack of trehalose catabolism in Sinorhizobium species increases their nodulation competitiveness on certain host genotypes. Ampomah OY, Jensen JB, Bhuvaneswari TV; New Phytol. 2008;179:495-504. PMID:19086182

3: The thuEFGKAB operon of rhizobia and agrobacterium tumefaciens codes for transport of trehalose, maltitol, and isomers of sucrose and their assimilation through the formation of their 3-keto derivatives. Ampomah OY, Avetisyan A, Hansen E, Svenson J, Huser T, Jensen JB, Bhuvaneswari TV; J Bacteriol. 2013;195:3797-3807. PMID:23772075