All the following pathogenic bacteria fulfill Kochs postulates except

Koch's postulates: A microorganism was accepted as the causative agent of infectious disease, only when it satisfied all the following criteria: 1. The microorganism must be present in every case of the disease but absent from healthy host. 2. The suspected microorganism must be isolated and grown in a pure culture from lesions of the disease. 3. The isolated organism, in pure culture, when inoculated in suitable laboratory animals should produce a similar disease. 4. The same microorganism must be isolated again in pure culture from the lesions produced in experimental animals. Most of the human bacterial pathogens satisfy Koch's postulates except for Mycobacterium leprae (leprosy) Treponema pallidum (syphilis) Both these bacteria are yet to be grown in cell-free culture media.