Cellular and Subcellular Organization of the 277F Agent, a Spiroplasma from the Rabbit Tick Haemaphysalis leporispalustris (Acari: Ixodidae)

Abstract

The cellular and subcellular ultrastructure of the helical 277F agent was studied in detail utilizing negative staining and ultrathin sections of fluids and/ or tissues of infected chicken embryos and Ornithodoros moubata ticks. This organism, which lacks a cell wall and axial filaments, conforms closely in size and fine structural characteristics (plasma membrane, ribosomes, fibrillar reticulum, and thin glycocalyx-like coat on the cell surface) to the genus Spiro-plasma of the order Mycoplasmatales.