Bacterial ABC transporters are essential in cell viability, virulence, and pathogenicity. Specific pathogens possess a wide array of virulence factors. A major group of virulence factors are bacterial toxins. These genes undergo intergenic recombination, further contributing to their virulence. Target prediction indicated possibility of sRNA interaction with several virulence genes. No human pathogens of comparable virulence have yet emerged from marine species. Pathogens may be intentionally or unintentionally genetically modified to change virulence and other characteristics. Bacterial small RNAs play critical roles in virulence and stress/adaptation responses. Yeast cells released from a biofilm have novel properties, including increased virulence and drug tolerance. Different strains exist which vary in their virulence. Another reason appears to be a lessening of the virulence or invasiveness of Streptococcus pyogenes. Slr1 plays a role in instigating hyphal formation and virulence in "C. albicans". It is a common means of spreading antibiotic resistance, virulence, and adaptive metabolic functions. It produces an emetic toxin, enterotoxins, and other virulence factors. Many of the bacteria's virulence factors are antiphagocytic in nature.