Epulopiscium spp., Metabacterium polyspora and the Segmented Filamentous Bacteria (SFB) form multiple intracellular offspring. For some of these bacteria, this process appears to be the only way to reproduce. Intracellular offspring development in these bacteria shares characteristics with endospore formation in Bacillus subtilis.
In large Epulopiscium spp. this unique reproductive strategy begins with asymmetric cell division, see The Epulopiscium Life Cycle Figure. Instead of placing the FtsZ ring at the center of the cell, as in binary fission, (A) Z rings are placed near both cell poles in Epulopiscium. (B) Division forms a large mother cell and two small offspring cells. (C) The smaller cells contain DNA and become fully engulfed by the larger mother cell. (D) The internal offspring grow within the cytoplasm of the mother cell. (E) Once offspring development is complete the mother cell dies and releases the offspring.
Our lab studies the mechanisms of intracellular offspring development in Epulopiscium and Metabacterium polyspora. We are interested in what mechanisms are conserved between these unusual reproductive processes and endospore formation. We hope to gain an understanding of how this novel form of cell reproduction developed over time and how it benefits these intestinal symbionts.
Some Selected Reviews about Division and Unusual Modes of Reproduction:
Alternatives to binary fission in bacteria. E. R. Angert. Nature Reviews Microbiology (2005) vol. 3, pp. 214-224.
Patterns of growth and development in pleurocapsalean cyanobacteria, J.B. Waterbury and R.Y. Stanier. Microbiological Reviews (1978) vol. 42, pp. 2-44.
Bacterial mitotic machineries. K. Gerdes, J. Møller-Jensen, G. Ebersbach, T. Kruse and K. Nordström. Cell (2004) vol. 116, pp. 359-366.
Bacterial cell division and the septal ring. D. S. Weiss. Molecular Microbiology (2004) vol. 54, pp. 588-597.