Research Interests

The focus of Huang lab is to isolate and characterize genes from microalgae for metabolic engineering of crop plants for high-yield production of high-value natural products, especially the ketocarotenoid astaxanthin and polyunsaturated fatty acids, such as DHA and EPA.

1.   Isolation and characterization of genes encoding enzymes for carotenoid and fatty acid biosynthesis

The group has cloned a number of genes involved in carotenoid and fatty acid biosynthesis from green microalgae, e.g., Haematococcus pluvialis (Huang et al., 2006a), Chlorella zofingiensis (Huang et al., 2006b; Huang et al., 2008; Liu et al, 2010; Huang et al., 2012; Liu et al., 2013).

2.   The biosynthesis and regulation of astaxanthin in green microalgae

Three carotenoid ketolase (BKT) genes were found in H. pluvialis, which are associated with the high contents of astaxanthin in the alga (Huang et al., 2006a). Whereas C. zofingiensis contains only one BKT gene (Huang et al., 2006b). The regulation of astaxanthin biosynthesis in the algae were studied in detail (Li et al., 2008, 2009).

3.   Metabolic engineering of higher plants for astaxanthin production

We have achieved significant progress on astaxanthin biosynthesis in higher plants. We isolated and characterized several algal β-carotene ketolases (BKT) and found that the BKT from Chlamydomonas reinhardtii could confer plant cells to efficiently synthesize astaxanthin (Zhong et al., 2011; Huang et al., 2012). Furthermore, we have generated a more nutritious tomato by modifying the intrinsic carotenes to astaxanthin by introducing the algal BKT gene into the genome of a B-type tomato (Huang et al., 2013). Massive accumulations of mostly free astaxanthin in leaves (3.12 mg/g) but esterified astaxanthin in fruits (16.1 mg/g) were found in the transgenic tomato, leading to a 16-fold increase of total carotenoid capacity in the fruits with above 80% of the carotenoids being astaxanthin. This achievement opened up the possibility of employing crop plants as green factories for economical production of astaxanthin.

4.   Microalgae as feedstock for biodiesel

We have searched for rapid growth, high lipid yields of microalgae as feedstock for the production of environmentally friendly biofuels. C. zofingiensis was assessed to be a candidate for such purposes (Liu et al., 2010a, b; 2011; 2012).