 Border-teller pertussis is known to produce a protein called FIM3, which can cause the bacteria to agglutinate when it is present at high concentrations. This phenomenon is known as autoagglutination. In this study, researchers isolated a mutant strain of B. Pertussis that did not produce FIM3, and found that it did not display the autoagglutination phenotype. They then used whole genome sequencing and immunoblotting to identify the gene responsible for the mutation, and discovered that it was located in the FIM3 promoter region. Further experiments showed that the mutation caused the deletion of a single C nucleotide from the promoter region, resulting in the absence of FIM3 production and the loss of the autoagglutination phenotype. Additionally, they found that the mutant strain had a lower level of FIM3 production compared to wild-type strains, suggesting that the mutation may have been selected for in the Japanese population due to its ability to reduce autoagglutination. Finally, they tested the frequency of autoagglutination in clinical B. Pertussis isolates collected. This article was authored by N. A. O. Otsuka, Kintorokoid, Masotokagoto, and others. We are article.tv, links in the description below.