Short Communication

Exposure to thermal stress induces overexpression of protein-L-iso aspartate-O-methyl transferase (PIMT) in Pseudomonas aeruginosa

Abstract

Background and Objectives: Apart from spontaneous deamidation and isomerization of Asp/Asn residues, factors like ageing, oxidative stress, salinity and heat stress may also form abnormal isoaspartate (iso-Asp) residues compromising protein structure and function. PIMT helps in restoration of such iso-Asp residues. Pseudomonas aeruginosa is a gram-negative bacteria responsible for diseases with varied degree of pathogenesis in humans and animals. They can survive a wide range of temperature between 25℃ to 42℃. The objective of the current study was to monitor the expression dynamics of PIMT in Pseudomonas aeruginosa upon exposure to different thermal stresses.
Materials and Methods: The mid log phase culture of Pseudomonas aeruginosa was exposed to different temperature (37°C, 42°C, 56°C, 80°C) for an hour. The expression levels of PIMT were quantified by Western blot and ELISA.
Results: A relatively higher level of expression of PIMT was observed in the group exposed to 42°C, 56°C, 80°C in comparison to 37°C. The expression of PIMT increased around 1.5 times in the group exposed to 42°C.
Conclusion: A temperature dependent overexpression of PIMT was observed in Pseudomonas aeruginosa.

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IssueVol 18 No 4 (2026) QRcode
SectionShort Communication
Keywords
Protein D-aspartate-L-isoaspartate methyltransferase Pseudomonas aeruginosa Heat stress Deamidation Enzyme-linked immunosorbent assay Western blotting
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How to Cite
1.
Agrawalla S, Mishra P, Sathapathy S, Kumar Sethi A, Dash D, Mahapatra A, Sahu R. Exposure to thermal stress induces overexpression of protein-L-iso aspartate-O-methyl transferase (PIMT) in Pseudomonas aeruginosa. Iran J Microbiol. 2026;18(4):629-632.