Revision as of 07:31, 22 October 2020

Candida albicans hyphal wall protein 1 (HWP1) gene

HWP1 is a Candida albicans cell surface protein gene. It is used in Candida albicans to mediate tight binding to oral epithelial cells. Hwp1 is covalently linked to cell wall glucan through a remnant of its GPI anchor. (Eukaryot Cell. 2006 October; 5(10): 1604–1610.) Hwp1 is known to cause biofilm formation in vivo in C. albicans.

We cloned HWP1 into the plasmid pCTCON2. We used homologous recombination and transformed it into EBY100 Yeast. We used pCTCON2 because it has Aga2, which helps express HWP1 on the surface of the yeast cell. pCTCON2 also has the pGal1 promoter so HWP1 is only expressed in the presence of Galactose. A TRP marker is used as a selectable marker to tell the difference between yeast cells with the pCTCON2 plasmid and yeast cells without the pCTCON2 plasmid. S. cerevisiae will express HWP1 in the presence of Galactose and will not when it isn't present.

2020 XHD-Wuhan-China’s Contribution

Sequence and Features

Usage and Biology

Using the pCTCON2 vector, we made a fusion protein of Hwp1 and Aga2, such that Hwp1 would be expressed and displayed on the surface of S. cerevisiae. pCTCON2 has a gal promoter such that the expression of Aga2-Hwp1 is controlled by the presence of galactose in the media. As shown below, only cells grown in the presence of galactose expressed Hwp1 and were able to adhere to one another in large clumps.

Figure 1: Control, non-induced Hwp1 expressing yeast. Dispersed, no major clustering.

Figure 2: Experiment, induced Hwp1 expressing yeast. 3-D cluster of yeast cells growing around and on top of other cells.

2020 XHD-Wuhan-China’s Contribution