Linked Life Data

10436088

Source:http://linkedlifedata.com/resource/pubmed/id/10436088

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1999-9-14
pubmed:abstractText
Polypeptide library screening technologies are critically dependent upon the characteristics of the expression system employed. A comparative analysis of the lpp-lac, tet and araBAD promoters was performed to determine the importance of tight regulation and expression level in library screening applications. The surface display of single-chain antibody (scFv) in Escherichia coli as an Lpp-OmpA' fusion was monitored using a fluorescently tagged antigen in conjunction with flow cytometry. In contrast to the lpp-lac promoter, both tet and araBAD promoters could be tightly repressed. Tight regulation was found to be essential for preventing rapid depletion of library clones expressing functional scFv and thus for maintaining the initial library diversity. Induction with subsaturating inducer concentrations yielded mixed populations of uninduced and fully induced cells for both the tet and araBAD expression systems. In contrast, homogeneous expression levels were obtained throughout the population using saturating inducer concentrations and could be adjusted by varying the induction time and plasmid copy number. Under optimal induction conditions for the araBAD system, protein expression did not compromise either cell viability or library diversity. This expression system was used to screen a library of random scFv mutants specific for digoxigenin for clones exhibiting improved hapten dissociation kinetics. Thus, an expression system has been developed which allows library diversity to be preserved and is generally applicable to the screening of E. coli surface displayed libraries.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0269-2139
pubmed:author
pubmed:issnType
Print
pubmed:volume
12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
613-21
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Development of an optimized expression system for the screening of antibody libraries displayed on the Escherichia coli surface.
pubmed:affiliation
Department of Chemical Engineering, Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.