The Curli protein is a type of amyloid fiber produced by certain strains of enterobacteria. It shares many structural and genomic similarities with Enterobacteria phage M13. Enterobacteria, pseudomonads and pathogenic moulds are resistant. However, because of the risk of overwhelming infections by enterobacteria, quinolones are preferred. There are currently many species in this genus including the type species Enterobacteria phage M13. The type species is Enterobacteria phage M13. As "B. bifidum" decreases, other gut bacteria such as "Lactobacilli", "Enterococci", "Enterobacteria" and "Clostridia" increase. Bacteria, including Enterobacteria, Caulobacter, Pseudomonas, and Acinetobacter serve as natural hosts for these bacteriophages. It has a relatively broad effect against gram-positive cocci but not against enterobacteria. Enterobacteria, intracellular parasitic bacteria, and spiroplasma serve as natural hosts. Enterobacteria phage T2, Enterobacteria phage T4 and Enterobacteria phage T2. Enterobacteria, caulobacter, pseudomonas, and acinetobacter serve as the natural host. Thus, "E. coli" and the other enterobacteria are important reservoirs of transferable antibiotic resistance. Enterobacteria serve as the natural host. Family N4 includes secreted virulence factors, or autotransporters, from enterobacteria.