Ribosomal DNA fingerprinting of diatom, genus Pseudo-nitzschia

Yeap, Han Soon (2005) Ribosomal DNA fingerprinting of diatom, genus Pseudo-nitzschia. Universiti Malaysia Sabah. (Unpublished)


Download (2MB) | Preview


The ribosomal DNA fingerprints of three strains of harmful algae, genus Pseudo-nitzschia designated PNA, PNB and PNC were examined. Harmful algae samples were collected from the coastal area of Sepanggar Bay, Sabah. The samples collected were cultured in suspension culture using L1 medium and the algae growth rate were monitored by doing cell counting. PNA reached the log phase after day 13 of culture, while PNB and PNC on day 14 and 16 respectively. Although PNC reached the log phase slower than the other two samples, it recorded more cells during the log phase compared to the other two. When the algae growth rate reached the log phase, DNA was extracted from each of the samples and amplified using primers targeting the small subunit of the rDNA through Polymerase Chain Reaction (PCR). Two PCR products with the size of 1,280 bp and 900 bp were obtained. Subsequently, the PCR products were subjected to restriction enzyme digestions by using Haelll. The digested DNA fragments of the three strains of samples showed that there were genetic differences among the three samples based on the number and size of digested fragments obtained. Four digested DNA fragments were observed in PNA and PNB while six digested fragments were observed in PNC. Degree of similarity calculated according to the Nei & Li (1979) similarity index showed that the degree of similarity between PNA and PNB was 1 and their genetic distance was 0. While the degree of similarity between PNC and these two strains was 0.8 and their genetic distance was 0.2. This showed that PNA and PNB were from the same strain, while PNC was a different strain from PNA and PNB. As a conclusion, in this study genetic molecular technique was found to be useful in identifying differences between algae strains.

Item Type: Academic Exercise
Uncontrolled Keywords: ribosomal, DNA fingerprint, harmful algae, genetic molecular, algae strain
Subjects: Q Science > QH Natural history > QH301 Biology
Divisions: SCHOOL > School of Science and Technology
Date Deposited: 11 Oct 2013 03:30
Last Modified: 17 Oct 2017 04:18
URI: http://eprints.ums.edu.my/id/eprint/7260

Actions (login required)

View Item View Item