Cultures of Tritrichomonas augusta, generously provided by Professor William Balamuth, were grown in Diamond's medium (6) modified by omission of agar. Because the organisms are anaerobic, the culture tubes were sealed with a mixture of vaseline and paraffin to exclude oxygen. 4-day cultures were fixed for 2 hr at 4°C in 5% glutaraldehyde-2% acrolein in 0.1 M cacodylate buffer with a final pH o...

Innate immunity has a key role in the control of microbial infections in both vertebrates and invertebrates. In insects, including vectors that transmit parasites that cause major human and animal diseases, antimicrobial peptides (AMPs) are important components of innate immunity. AMPs are induced upon parasitic infections and can participate in regulating parasite development in the digestive ...

The mitochondrial DNA (mtDNA) of a primitive kinetoplastid flagellate Cryptobia helicis is composed of 4.2 kb minicircles and 43 kb maxicircles. 85% and 6% of the minicircles are in the form of supercoiled (SC) and relaxed (OC) monomers, respectively. The remaining minicircles (9%) constitute catenated oligomers composed of both the SC and OC molecules. Minicircles contain bent helix and sequen...

The plastid genome of the colorless, nonphotosynthetic protist Astasia longa resembles that of the photoautotrophic species Euglena g r a d i s but is only half the size (73 kb instead of 143 kb). A large number of intact ribosomal protein genes, rRNA genes, and tRNA genes have been identified in the 50% of Astasia ptDNA that has been sequenced (Siemeister and Hachtel, 1989; Siemeister et al., ...

The structure of the nuclear and cytoplasmic membranes of Trichonympha, a complex flagellate, has been studied in the electron microscope. The nuclear membrane consists of two 70 A membranes, penetrated by numerous pores. Small (100 A) granules occur on the outer surface, around the rims of the pores. Granule-bearing membranes, only 30 to 40 A thick, form long, ribbon-shaped sacs, with 100 A gr...