Reassessing the Standard Chemotaxis Framework for Understanding Biased Migration in .

infections are a major cause of peptic ulcers and gastric cancers. The development of robust inflammation in response to these flagellated, motile bacteria is correlated with poor prognosis. Chemotaxis plays a crucial role in colonization, enabling the bacteria to swim toward favorable chemical environments. Unlike the model species of bacterial chemotaxis, , cells possess polar flagella. They run forward by rotating their flagella counterclockwise, whereas backward runs are achieved by rotating their flagella clockwise. We delve into the implications of certain features of the canonical model of chemotaxis on our understanding of biased migration in polarly flagellated bacteria such as . In particular, we predict how the translational displacement of cells during a backward run could give rise to chemotaxis errors within the canonical framework. Also, lack key chemotaxis enzymes found in , without which sensitive detection of ligands with a wide dynamic range seems unlikely. Despite these problems, exhibit robust ability to migrate toward urea-rich sources. We emphasize various unresolved questions regarding the biophysical mechanisms of chemotaxis in , shedding light on potential directions for future research. Understanding the intricacies of biased migration in could offer valuable insights into how pathogens breach various protective barriers in the human host.