New knowledge about the virulence and resistance of hospital superbug

Irfan Ahmad, Department of molecular biology at Umeå University.

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valuable insights for development of new therapeutic strategies to treat and prevent infections caused by this bacterium

“Our findings contribute to better understanding of molecular mechanisms underlying virulence by A. baumannii and offer valuable insights for development of new therapeutic strategies to treat and prevent infections caused by this bacterium”, says Irfan Ahmad, who has been visiting Associate Professor at Department of Molecular Biology at Umeå University and is corresponding author of the study.

Antibiotic-resistant Acinetobacter baumannii bacteria has become a global health threat that causes many serious infections, especially among patients in hospital environments. The bacteria is ranked highest priority by the WHO when it comes to the need for new antibiotics and the development of alternative means to counteract the infections.

Adhesion to various types of surfaces through the production of pili, filaments of protein polymers on its surface, is one of the properties of the superbug that greatly contributes to its ability to establish itself and to colonize various tissues that can lead to infection. 

In the new study, Irfan Ahmad and his team at Umeå University, in collaboration with colleagues at the University of Health Sciences, Lahore in Pakistan, and the University of Turku in Finland, investigated the role of Csu pili of A. baumannii in the bacterial colonisation of host cells and tissues.

Their findings revealed that when clinical isolates of A. baumannii express such pili abundantly, they contribute to formation of mountain-like biofilm patches that are causing elevated tolerance to antibiotics, including the important last line antibiotic colistin.

“Moreover, the Csu pili are not only a functional component of mature A. baumannii biofilms but also a major virulence factor promoting the initiation of disease progression by mediating bacterial adherence to epithelial cells”, says Irfan Ahmad.

About the scientific publication:

Ahmad, I., Nadeem, A., Mushtaq, F., Zlatkov, N., Shahzad, M., Zavialov, A.A., Wai, S.N., Uhlin, B.E. Csu pili dependent biofilm formation and virulence of Acinetobacter baumannii. npj Biofilms Microbiomes 9, 101 (2023).