Isolation of bacterial strains capable of efficient conversion of n-alkanes into value added products

Bacteria that are capable of degrading alkane fractions, C12-C13 and C14-C17, were isolated from oil-contaminated soil collected from the petrochemical company, CALTEX Refineries, South Africa. A total of twenty-three environmental strains were isolated. A preliminary procedure, Nile Blue A straining suggested that twelve of the twenty-three environmental strains might accumulate polyhydroxyalkanoates (PHAs) in their cytoplasm, which is a good candidate for biodegradable plastics. The gene that catalyzes PHA polymerization, phaC, was detected using PCR in some of the environmental strains. The strains of interest were identified and characterized biochemically using various techniques and later sequenced by 16S rONA PCR. The environmental isolate 2 showed a 99 % identity to Pseudomonas aeruginosa BHP7 -6 and was for that reason given a name, Pseudomonas aeruginosa MB2SA. P. aeruginosa MB2SA was shown to possess a 0.5 kb internal fragment corresponding to the phaC gene and capable of degrading the alkane fractions, Cn-CI3 and CI4-CI7, effectively. P. aeruginosa MB2SA was shown to grow optimally in the long alkane fraction, Cw C17, and was further grown in pure alkanes, n-dodecane, n-tetradecane, and hexadecane for comparison. In addition, the strain, P. aeruginosa MB2SA, was grown in an appropriate medium for PHA synthesis and high yields of PHA were observed when both the long alkane fraction, Cw CI7, and pure alkane, hexadecane, were employed as sole carbon sources respectively.

Grantor dc:publisher.institution

Department of Molecular and Cell Biology

Year dc:date.issued

2004

Author dc:creator

• Mathopa, Byatlela Abel

Advisor dc:contributor.advisor

• Reid, Sharon J

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/4294

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/4294