Review Question - QID 213703

A 41-year-old homeless man presents to the emergency department with a low-grade fever for 1 month. He says that he has been feeling general malaise and wakes up at night covered in sweat. He also has severe back pain in the thoracic region that has been getting worse over the last 3 months. Finally, he says that he had a cough that produced bloody sputum. His past medical history is significant for diabetes, sickle cell disease, and poorly controlled HIV. Physical exam reveals tenderness over the T5 vertebra, and a radiograph of the spine shows kyphosis associated with preserved disk space and vertebral body collapse. Which of the following is a virulence factor associated with the most likely cause of this disease?