Marine hydrocarbonoclastic bacteria as whole‐cell biosensors for n‐alkanes. Issue 4 (15th April 2015)

• Record Type: Journal Article
• Authors: Sevilla, Emma; Yuste, Luis; Rojo, Fernando
• Is Part Of: Microbial biotechnology. Volume 8:Issue 4(2015:Jul.)
• Page Start: 693
• Page End: 706
• Publication Date: 2015-04-15
• Subjects: Microbial biotechnology -- Periodicals; Biotechnology; Microbiology; 660.62
• DOI: 10.1111/1751-7915.12286
• Languages: English
• ISSNs: 1751-7915

Abstract

<abstract abstract-type="main"> <title>Summary</title> <p>Whole‐cell biosensors offer potentially useful, cost‐effective systems for the <italic>in‐situ</italic> monitoring of seawater for hydrocarbons derived from accidental spills. The present work compares the performance of a biosensor system for the detection of alkanes in seawater, hosted in either <italic>E</italic><italic>scherichia coli</italic> (commonly employed in whole‐cell biosensors but not optimized for alkane assimilation) or different marine bacteria specialized in assimilating alkanes. The sensor system was based on the <italic>P</italic><italic>seudomonas putida</italic> AlkS regulatory protein and the <italic>PalkB</italic> promoter fused to a gene encoding the green fluorescent protein. While the <italic>E</italic><italic>. coli</italic> sensor provided the fastest response to pure alkanes (25‐fold induction after 2 h under the conditions used), a sensor based on <italic>A</italic><italic>lcanivorax borkumensis</italic> was slower, requiring 3–4 h to reach similar induction values. However, the <italic>A</italic><italic>. borkumensis</italic> sensor showed a fourfold lower detection threshold for octane (0.5 μM), and was also better at sensing the alkanes present in petrol. At petrol concentrations of 0.0125%, the <italic>A</italic><italic>. borkumensis</italic> sensor rendered a sevenfold induction, while <italic>E</italic><italic>. coli</italic> sensor showed no response. We discuss possible explanations to this behaviour in terms of the cellular adaptations to alkane uptake and the basal fluorescence produced by each bacterial strain, which was lowest for <italic>A</italic><italic>. borkumensis</italic>.</p> </abstract>