Quantitative analysis used in L. lactis study

Scientists have used quantitative analysis to identify solutions to problems associated with protein over-expression in Lactococcus lactis subsp. Cremoris (L. lactis).

In the development of the Nisin Inducible Controlled Expression (NICE) system, the food grade bacterium L. lactis represents a cornerstone in the use of Gram-positive bacterial expression systems for biotechnological purposes.

However, this does have its problems, as proteins that are subjected to this over-expression in L. lactis can suffer from improper folding, inclusion body formation and/or protein degradation, which can significantly reduce the yield of soluble target protein.

In a study published by Microbial Cell Factories journal, the team used quantitative analysis processes to identify the first description of a thioredoxin gene fusion expression system, purposely developed to evade problems associated with protein over-expression in L. lactis.

"Although our study does not show the functionality of the over-expressed proteins, we are confident that the majority of such proteins are biologically active as based on numerous peer-reviewed studies using the original NICE system," the report claimed.