title: Comparison of cellular stress levels and green-fluorescent-protein expression in several Escherichia coli strains.
abstract: Constructs comprising stress-gene promoter elements from rpoH (Sigma 32), clpB or dnaK linked to a green-fluorescent-protein (GFP) expression vector were previously used as non-invasive "stress probes" in Escherichia coli. We compared cellular stress responses in four E. coli strains: production hosts JM105 and BL21, and cloning hosts HB101 and TOP10. When GFP was also used as a model for foreign protein production, we generally observed that the level of expression was inversely proportional to the level of cellular stress. JM105 showed the highest cellular stress level and very low GFP expression, while BL21 exhibited the lowest cellular stress level and the highest GFP expression, in both normal and heat-shock stress environments.
authors.affiliation: Department of Chemical Engineering & Division of Molecular and Life Sciences, Pohang University of Science and Technology, Pohang 790-784, South Korea.
authors.forename: Jeong Hyun
authors.initials: JH
authors.lastname: Seo
authors.forename: Dong Gyun
authors.initials: DG
authors.lastname: Kang
authors.forename: Hyung Joon
authors.initials: HJ
authors.lastname: Cha
mesh_terms: D004926:Escherichia coli / Q000145:classification / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D018869:Heat-Shock Response / Q000502:physiology*; D006358:Hot Temperature; D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D013045:Species Specificity
chemical_list: D006360:Heat-Shock Proteins; D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins