Developing DNA barcodes of harmful marine microalgae in Malaysia

• Main Author: Cheng, Sue Lin.
• Format: Final Year Project Report
• Language: English
• Published: Universiti Malaysia Sarawak (UNIMAS) 2014
• Subjects: Q Science (General); QH Natural history
• Online Access: http://ir.unimas.my/id/eprint/23721/2/Developing%20DNA%20barcodes%20of%20harmful%20marine%20microalgae%20in%20Malaysia%20%28fulltext%29.pdf; http://ir.unimas.my/id/eprint/23721/

Morphological identification of microalgae species are required expertise in the taxonomy and well-trained skills in advanced microscopy. A new molecular tool, DNA barcode is widely used as molecular-based identification system that aims to identify biological species and to group them to a given species. Harmful microalgae are harmful and toxic to the marine lifes. Human being also affected by the intoxication of harmful algal blooms (HABs). In this study, DNA barcoding is developed to characterize the species of harmful microalgae to ease the monitoring purposes. The second internal transcribed spacer (ITS2) of the nuclear encoded ribosomal DNA (rDNA) is used as the potential barcode coupled with its secondary structural information. In brief, the study involved plankton sampling that is undertaken by plankton net hauls from the coastal waters of Malaysia and Singapore in order to establish new cultures of harmful marine microalgae species found in both waters. Preserved plankton samples are examined by using scanning electron microscope and light microscope to obtain morphology of the species. Single-cell PCR is performed using saline ethanolpreserved natural samples. Clonal cultures are established from live samples collected. Gene amplification is performed to amplify the ITS region on culture samples. Homologous modeling and free energy minimization approaches are used to model the ITS2 secondary structure of the harmful microalgae found in Malaysian waters. Sequence signatures of species found is assigned for DNA barcoding. In the end of this study, detailed morphology of the harmful microalgae as well as their DNA barcode are obtained.