ABSTRACT
In this chapter, the authors investigate incorporation and metabolism of the chitin precursor N-acetylglucosamine by the MRRL-CH cell line derived from embryos of the lepidopteran insect, Manduca sexta L. Cell lines MRRL-CH and MRRL-CH2 were derived from embryos of M. sexta grown in T. D. C. Grace's modified medium supplemented with 15% fetal bovine serum. Examination of the cultures in which the cuticle spheres were found revealed numerous cell aggregates about the same size as the cuticle spheres and delicate membranes from partially formed cuticle spheres. Uptake of N-acetylglucosamine (GlcNAc) was measured in several experiments. Cuticle spheres were found in freshly thawed cultures of both MRRL-CH and MRRL-CH2 lines. To determine whether the uptake and retention of GlcNAc required an energy source, effects of inhibitors of cellular respiration were tested. Taken together with results obtained with the original solvent system, it is clear that GlcNAc was taken up from the medium and incorporated into several products.
