Genomic Insights into Ceftazidime Resistance in Burkholderia pseudomallei: Discovery of A172T Mutation, and Palindromic GC-Rich Repeat Sequences Facilitating penA Duplication and Amplification.

Tuanyok, A.; Nakajima, C.; Noll, T.; Khan, M. S.; Khrongsee, P.; Yowell, C. A.; Xiao, Y.-P.; Wuthiekanun, V.; Chantratita, N.; Heine, H.; Subramaniam, K.; Suzuki, Y.; Limmathurotsaku, D.; Mergia, A.

doi:10.1101/2025.02.11.637714

bioRxiv · 10.1101/2025.02.11.637714

Genomic Insights into Ceftazidime Resistance in Burkholderia pseudomallei: Discovery of A172T Mutation, and Palindromic GC-Rich Repeat Sequences Facilitating penA Duplication and Amplification.

Tuanyok, A.·Nakajima, C.·Noll, T.·Khan, M. S.·Khrongsee, P.·Yowell, C. A.·Xiao, Y.-P.·Wuthiekanun, V.·Chantratita, N.·Heine, H.·Subramaniam, K.·Suzuki, Y.·Limmathurotsaku, D.·Mergia, A.

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Abstract

Ceftazidime (CAZ) resistance in Burkholderia pseudomallei, the causative agent of melioidosis, complicates treatment in endemic regions. This study identified a novel A172T mutation and other known penA mutations as critical contributors to CAZ resistance in a large Thai strain collection. Frequent gene duplication and amplification (GDA) of penA, likely driven by Palindromic GC-Rich Repeat Sequences (PGCRRS), highlights the urgent need for rapid diagnostics and optimized treatment strategies to manage this life-threatening disease effectively.

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Tuanyok, A., Nakajima, C., Noll, T., Khan, M. S., Khrongsee, P., Yowell, C. A., Xiao, Y.-P., Wuthiekanun, V., Chantratita, N., Heine, H., Subramaniam, K., Suzuki, Y., Limmathurotsaku, D., Mergia, A.. 2025-02-11. Genomic Insights into Ceftazidime Resistance in Burkholderia pseudomallei: Discovery of A172T Mutation, and Palindromic GC-Rich Repeat Sequences Facilitating penA Duplication and Amplification.. https://doi.org/10.1101/2025.02.11.637714

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