Identification of a novel mutation of sat (Gly82Arg) in Shigella flexneri serotype 7a: insights into clinical relevance

Nisa I, Qasim M, Driessen A, Nijland J, Rahman H, Yousafzai YM, Alzahrani KJ, Mattner J, Muhammad N, Bari F, Khan TA (2026)

Publication Type: Journal article

Publication year: 2026

Journal

Folia Microbiologica Springer Verlag (Germany)

DOI: 10.1007/s12223-026-01484-4

Abstract

Virulence factors can vary between Shigella (S.) flexneri serotypes. The current study characterized virulence genes among 199 S. flexneri from different serotypes in Peshawar, Khyber Pakhtunkhwa Province, Pakistan, by sequence analysis. Moreover, using the homology model, the 3D protein structure of the serine autotransporter toxin (sat) from S. flexneri was examined for the first time to determine structural changes in the mutant sat protein. Interestingly, the present study reported that ial(spa29/spaR) gene has not shown any relationship to the previously known sequence of S. flexneri, but it has a striking resemblance to previously reported cases that were identified in Shigella dysenteriae and Escherichia coli. Furthermore, 15 strains of S. flexneri, all of which are members of serotype 7a, were found to carry the single-point mutation (G246A) in sat, which resulted in an exchange of amino acid (Gly82Arg). Preliminary data reveal a potential link between the sat gene mutation and severe clinical illness patients; however additional study is needed to verify this relation. Overall, the results of the mutant sat proteins homology model validation showed a slight, but not significant, alteration in protein structure.

Authors with CRIS profile

Jochen Mattner Institute of Microbiology – Clinical Microbiology, Immunology and Hygiene

Involved external institutions

University of Groningen / Rijksuniversiteit Groningen NL Netherlands (NL) Abdul Wali Khan University Mardan PK Pakistan (PK) Khyber Medical University / جامعہ طبی خیبر‎ PK Pakistan (PK) Taif University / جامعة الطائف SA Saudi Arabia (SA) Kohat University of Science & Technology PK Pakistan (PK) Rehman Medical College (RMC) PK Pakistan (PK) Women University Swabi (WUS) PK Pakistan (PK)

How to cite

APA:

Nisa, I., Qasim, M., Driessen, A., Nijland, J., Rahman, H., Yousafzai, Y.M.,... Khan, T.A. (2026). Identification of a novel mutation of sat (Gly82Arg) in Shigella flexneri serotype 7a: insights into clinical relevance. Folia Microbiologica. https://doi.org/10.1007/s12223-026-01484-4

MLA:

Nisa, Iqbal, et al. "Identification of a novel mutation of sat (Gly82Arg) in Shigella flexneri serotype 7a: insights into clinical relevance." Folia Microbiologica (2026).

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