Chitinous fibrils in the lorica of the flagellate chrysophyte Poteriochromonas stipitata (syn. Ochromonas malhamensis).

Abstract

Ordered microfibrils are formed on the membrane of the cytoplasmic tail of the alga Poteriochromonas after attachment to a substrate. The ultrastructure of native and extracted stalk fibrils was studied with EM methods. The structural polysaccharide was characterized by hydrolyses, separation of the monomers by TLC, GLC and amino acid analysis, and by X-ray diffraction. The alkali-resistant fibrils yielded mostly glucosamine on extensive hydrolysis, and showed X-ray diffraction patterns similar to those of fugal chitin. Apparently the resistant core of the fibrils is chitinous.