Biomedical Sciences Graduate Program | University of California, San Francisco

Creg Darby, PhD
Biofilms of pathogenic bacteria
Epigenetic paternal inheritance in C. elegans

Selected Publications | Complete Publications

phone	(415) 476-3104
email	creg.darby@ucsf.edu
additional websites
secondary research affiliation	Human Genetics

A biofilm is a microbial population that produces an extracellular matrix and uses it to adhere to a surface. The bubonic plague (Black Death) bacterium Yersinia pestis makes a biofilm to colonize its vector, the flea. The biofilm blocks the flea’s digestive tract and starves the insect, stimulating it to bite repeatedly in futile attempts to feed, and the bites spreads bacteria to new hosts. Because Y. pestis biofilms also block feeding of the nematode Caenorhabditis elegans, we are able to use this easily manipulated laboratory worm as a surrogate for fleas. In Y. pestis we are determining the genetic pathways of Y. pestis biofilm synthesis, and simultaneously we are using C. elegans genetics to understand the host role in biofilm adhesion.

A new project is investigating the role of Lactobacilli in aggressive early childhood caries (tooth decay).

Selected Publications

Yi-Cheng Sun, B. Joseph Hinnebusch and Creg Darby (2008) Experimental evidence for negative selection in the evolution of a Yersinia pestis pseudogene. Proceedings of the National Academy of Sciences USA 105:8097-8101.

Creg Darby (2008) Uniquely insidious: Yersinia pestis biofilms. Trends in Microbiology 16:158-64.

Creg Darby, Amrita Chakraborti, Samuel M. Politz, Calvin C. Daniels, Li Tan and Kevin Drace (2007) Caenorhabditis elegans Mutants Resistant to Attachment of Yersinia sp. Biofilms. Genetics 176:221-30.

Li Tan and Creg Darby (2006) Yersinia pestis YrbH is a multi-functional protein required for both 3-deoxy-d-manno-oct-2-ulosonic acid biosynthesis and biofilm formation. Molecular Microbiology 61:861-70.

Li Tan and Creg Darby (2005) Yersinia pestis is Viable with Endotoxin Composed of Only Lipid A. Journal of Bacteriology 187:6599-6600.

Creg Darby, Sandya L. Ananth, Li Tan and B. Joseph Hinnebusch (2005) Identification of gmhA, a Yersinia pestis Gene Required for Flea Blockage, Using a Caenorhabditis elegans Biofilm System. Infection and Immunity 73:7236-42.

Li Tan and Creg Darby (2004) A Movable Surface: Formation of Yersinia sp. Biofilms on Motile Caenorhabditis elegans. Journal of Bacteriology 186:5087-92.

Creg Darby, Jennifer W. Hsu, Nafisa Ghori and Stanley Falkow (2002) Caenorhabditis elegans: Plague bacteria biofilm blocks food intake. Nature 417:243-4.

Creg Darby and Stanley Falkow (2001) Mimicry of a G Protein Mutation by Pertussis Toxin Expression in Transgenic Caenorhabditis elegans. Infection & Immunity 69:6271-75.

Creg Darby, Christine L. Cosma, James H. Thomas and Colin Manoil (1999) Lethal paralysis of Caenorhabditis elegans by Pseudomonas aeruginosa. Proceedings of the National Academy of Sciences USA 96:15202-7.

updated July 2008