According to this
PAMPs are delivered along with additional information that can be used by the host to distinguish pathogenic from nonpathogenic microbes and thereby guide the ensuing innate immune response.
Does this statement mean that non-pathogenic bacteria do not have PAMPs? If yes, then how would the host body differentiate between a pathogenic and a non-pathogenic microbe? Is there any well-known source containing a list of non-pathogenic microbes? Are there any research paper which proves that a certain microbe is non-pathogenic?