Dergiler / Turkish Journal of Biology / 2015 / Cilt: 39 - Sayı: 3
Investigation of the in vivo interaction between Ã-lactamase and its inhibitor protein
- Sayfa
- 485–492
- DOI
- —
Özet
The affinity of Ã-lactamase inhibitory protein (BLIP) for TEM-1 Ã-lactamase has raised hopes in the challenge of protein-based inhibitor discovery for Ã-lactamase-mediated antibiotic resistance. Currently, the effect of the formation of the Ã-lactamase:BLIP complex in vivo in Ã-lactam resistant bacteria is an open question. The scarcity of information to the extent to which BLIP can impair Ã-lactamase activity inside cells has urged us to assess the in vivo efficacy of BLIP as a potent Ã-lactamase inhibitor. To this end, Ã-lactamase and BLIP were coexpressed in Escherichia coli. Simultaneous expression of Ã-lactamase and BLIP and the formation of the TEM-1 Ã-lactamase:BLIP complex in the periplasmic space of E. coli were verified by electrophoretic and Western blot techniques. Growth profiles of the cells expressing both Ã-lactamase and its protein inhibitor, complemented with Ã-lactamase activity measurements, suggested that BLIP synthesis retarded cell growth and reduced Ã-lactamase activity. Although co-expression of Ã-lactamase and its protein inhibitor did not completely impair cell growth, the specificity of BLIP enabled it to bind Ã-lactamase in the bacterial periplasm, regardless of the crowding components.
Abstract
The affinity of Ã-lactamase inhibitory protein (BLIP) for TEM-1 Ã-lactamase has raised hopes in the challenge of protein-based inhibitor discovery for Ã-lactamase-mediated antibiotic resistance. Currently, the effect of the formation of the Ã-lactamase:BLIP complex in vivo in Ã-lactam resistant bacteria is an open question. The scarcity of information to the extent to which BLIP can impair Ã-lactamase activity inside cells has urged us to assess the in vivo efficacy of BLIP as a potent Ã-lactamase inhibitor. To this end, Ã-lactamase and BLIP were coexpressed in Escherichia coli. Simultaneous expression of Ã-lactamase and BLIP and the formation of the TEM-1 Ã-lactamase:BLIP complex in the periplasmic space of E. coli were verified by electrophoretic and Western blot techniques. Growth profiles of the cells expressing both Ã-lactamase and its protein inhibitor, complemented with Ã-lactamase activity measurements, suggested that BLIP synthesis retarded cell growth and reduced Ã-lactamase activity. Although co-expression of Ã-lactamase and its protein inhibitor did not completely impair cell growth, the specificity of BLIP enabled it to bind Ã-lactamase in the bacterial periplasm, regardless of the crowding components.