Characterisation of trehalose-6-phosphate phosphatases from bacterial pathogens

• Published in: Biochimica et biophysica acta. Proteins and proteomics Vol. 1869; no. 2; p. 140564
• Main Authors: Kim, Jun-Hong, Kim, Ji-Won, Jo, Jiwon, Straub, Jan Hendrik, Cross, Megan, Hofmann, Andreas, Kim, Jeong-Sun
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.02.2021
• Subjects: Acinetobacter baumannii - enzymology; Acinetobacter baumannii - pathogenicity; Bacterial Infections - enzymology; Bacterial Infections - genetics; Bacterial Infections - microbiology; Catalyis; Catalytic Domain - genetics; Cooperativity; Corynebacterium diphtheriae - enzymology; Corynebacterium diphtheriae - pathogenicity; Enzyme activity; Glucosyltransferases - chemistry; Glucosyltransferases - genetics; Halo-acid dehydrogenase; Humans; Multi-drug resistance; Protein structure-function; Pseudomonas stutzeri - enzymology; Pseudomonas stutzeri - pathogenicity; Sugar Phosphates - genetics; Sugar Phosphates - metabolism; Trehalose - analogs & derivatives; Trehalose - biosynthesis; Trehalose - genetics; Trehalose - metabolism; Multi-drug resistance; Enzyme activity; Cooperativity; Catalyis; Protein structure-function; Halo-acid dehydrogenase
• ISSN: 1570-9639; 1878-1454
• DOI: 10.1016/j.bbapap.2020.140564

The trehalose biosynthesis pathway has recently received attention for therapeutic intervention combating infectious diseases caused by bacteria, helminths or fungi. Trehalose-6-phosphate phosphatase (TPP) is a key enzyme of the most common trehalose biosynthesis pathway and a particularly attractive target owing to the toxicity of accumulated trehalose-6-phosphate in pathogens. Here, we characterised TPP-like proteins from bacterial pathogens implicated in nosocomial infections in terms of their steady-state kinetics as well as pH- and metal-dependency of their enzymatic activity. Analysis of the steady-state kinetics of recombinantly expressed enzymes from Acinetobacter baumannii, Corynebacterium diphtheriae and Pseudomonas stutzeri yielded similar kinetic parameters as those of other reported bacterial TPPs. In contrast to nematode TPPs, the divalent metal ion appears to be bound only weakly in the active site of bacterial TPPs, allowing the exchange of the resident magnesium ion with other metal ions. Enzymatic activity comparable to the wild-type enzyme was observed for the TPP from P. stutzeri with manganese, cobalt and nickel. Analysis of the enzymatic activity of S. maltophilia TPP active site mutants provides evidence for the involvement of four canonical aspartate residues as well as a strictly conserved histidine residue of TPP-like proteins from bacteria in the enzyme mechanism. That histidine residue is a member of an interconnected network of five conserved residues in the active site of bacterial TPPs which likely constitute one or more functional units, directly or indirectly cooperating to enhance different aspects of the catalytic activity. •Trehalose-6-phosphate phosphatase (TPP) is a target to combat infectious diseases.•Bacterial TPPs constitute a distinguished group among mono-enzyme TPPs.•In contrast to other TPPs, the divalent metal ion is bound only weakly in bacterial TPPs.•A strictly conserved histidine residue of bacterial TPPs is involved in the enzyme mechanism.•A network of conserved residues constitutes an interconnected functional unit in the active site.