P. luminescens affects C. elegans intestinal cells . (A) Nomarski DIC images of C. elegans intestine fed on E. coli (A, B) or P. luminescens (C, D) for 44 hours. (A) Uterus region. Arrowheads indicate healthy intestinal lumen. (B) Tail region. (C) Uterus region. Intestinal cells are delicate and pseudocoelomic space becomes larger (asterisk). Arrows indicate crystal-like structures constructed in the intestinal lumen. (D) Tail region. Arrow indicates crystal-like structures constructed in the intestinal lumen. Anterior is left. Scale bars, 50 μm.