Sequencing analysis and efficient biodiesel production by lipase from Pseudomonas aeruginosa

BACKGROUND

Recently, lipase processing for biodiesel production has shown a global increase as it is considered a potential alternative clean-fuel source. The current study's objective is to investigate of lipolytic activity of lipase produced from different strains of Pseudomonas aeruginosa (P. aeruginosa) in biodiesel production using edible plant oils. The goal is to develop an efficient and cost-effective method for producing inexpensive and environmentally friendly biodiesel.

METHODS AND RESULTS

Four P. aeruginosa isolates were obtained from different environmental sources (soil), phenotypically identified, and it was confirmed by the PCR detection of the 16SrRNA gene. The isolated P. aeruginosa strains were screened for lipase production, and the recovered lipase was purified. Besides, the lipase (lip) gene was detected by PCR, and the purified PCR products were sequenced and analyzed. The production of biofuel was conducted using gas chromatography among tested oils. It was found that castor oil was the best one that enhances lipase production in-vitro.

The lip gene contributes to the virulence of Aeromonas veronii strain TH0426

Aeromonas veronii (A. veronii) is a pathogen that can infect aquatic organisms and mammals and has caused irrecoverable economic losses to the aquaculture industry. The results of an epidemiological investigation showed that the number of cases of A. veronii have increased gradually in recent years, and its drug resistance and virulence has shown an upward trend. In this study, we constructed an A. veronii mutant strain Δlip, by homologous recombination and studied its function. The results showed that there was no significant difference in the biofilm formation ability between the Δlip and the wild-type strain, but the toxicity of the Δlip to EPC cells and its ability to adhere to EPC cells were significantly reduced. The LD₅₀ value of the Δlip to zebrafish was 7.40-fold higher than that of the wild-type strain. In addition, after 24 h and 72 h, the bacterial loads of the Δlip in the organs of crucian carp were significantly lower than those in the wild-type strain. In conclusion, the mutant strain Δlip led to a decrease in the adhesion and virulence of the wild-type strain, which lays a foundation to further understand lip gene function and the pathogenic mechanism of A. veronii.