Solanum lycopersicum heme-binding protein 2 as a potent antimicrobial weapon against plant pathogens

Sci Rep. 2023 Nov 20;13(1):20336. doi: 10.1038/s41598-023-47236-z.

Abstract

The rise in antibiotic-resistant bacteria caused by the excessive use of antibiotics has led to the urgent exploration of alternative antimicrobial solutions. Among these alternatives, antimicrobial proteins, and peptides (Apps) have garnered attention due to their wide-ranging antimicrobial effects. This study focuses on evaluating the antimicrobial properties of Solanum lycopersicum heme-binding protein 2 (SlHBP2), an apoplastic protein extracted from tomato plants treated with 1-Methyl tryptophan (1-MT), against Pseudomonas syringae pv. tomato DC3000 (Pst). Computational studies indicate that SlHBP2 is annotated as a SOUL heme-binding family protein. Remarkably, recombinant SlHBP2 demonstrated significant efficacy in inhibiting the growth of Pst within a concentration range of 3-25 μg/mL. Moreover, SlHBP2 exhibited potent antimicrobial effects against other microorganisms, including Xanthomonas vesicatoria (Xv), Clavibacter michiganensis subsp. michiganensis (Cmm), and Botrytis cinerea. To understand the mechanism of action employed by SlHBP2 against Pst, various techniques such as microscopy and fluorescence assays were employed. The results revealed that SlHBP2 disrupts the bacterial cell wall and causes leakage of intracellular contents. To summarize, the findings suggest that SlHBP2 has significant antimicrobial properties, making it a potential antimicrobial agent against a wide range of pathogens. Although further studies are warranted to explore the full potential of SlHBP2 and its suitability in various applications.

MeSH terms

  • Anti-Infective Agents* / pharmacology
  • Clavibacter
  • Heme-Binding Proteins
  • Plant Diseases / microbiology
  • Plant Diseases / prevention & control
  • Pseudomonas syringae
  • Solanum lycopersicum*

Substances

  • Heme-Binding Proteins
  • Anti-Infective Agents

Supplementary concepts

  • Clavibacter michiganensis subsp. michiganensis