Strategies for enhancing bioluminescent bacterial sensor performance by promoter region manipulation.
Bottom Line: By manipulating the length of the promoter-containing segment (both promoters), by introducing random or specific mutations in the promoter sequence or by duplicating the promoter sequence (sulA only), major improvements in sensor performance were obtained.Improvements included significantly enhanced sensitivity, earlier response times and an increase in signal intensity.The general approaches described herein may be of general applicability for optimizing bacterial sensor performance, regardless of the sensing or reporting elements employed.
Affiliation: Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.Show MeSH
Related in: MedlinePlus
Mentions: Out of nearly a thousand colonies screened in this manner, one improved mutant (sulA18) was selected. This mutant exhibited a much faster and stronger response to NA (Fig. 2A), the latter effect evidenced by dramatically higher ΔRLU values (Fig. 2B). This difference was also apparent when quantified by the response ratio (Fig. 2C). However, as bioluminescence background emission of the sulA18 mutant was significantly higher than that of the wild type also in the non‐induced control (at time zero, c. 1100 versus 250 RLU respectively), the effect on the response ratio was less dramatic than that evidenced by the ΔRLU. As shown in Table 1, the sulA18 mutant also displayed an enhanced sensitivity, with an EC200 value of 1.5 mg l−1 as compared with 4 in the wild type.
Affiliation: Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.