The Escherichia coli colanic acid capsule produced by the cps gene confers resistance in the presence of sublethal antibiotic concentrations. However, the exact mechanism of capsule gene regulation in reaction to the presence of antibiotics is unknown.
Current JEMI Papers
The Rcs Phosphorelay May Regulate the E. coli Capsule In Response to Sublethal Streptomycin Treatment
Quantitative Polymerase Chain Reaction Assay to Study the Role of Genetic Elements Involved in Regulating Plasmid Copy Number
We have created a quantitative polymerase chain reaction (qPCR) assay that can measure relative plasmid copy number. The assay uses a calibrator plasmid, pCHCS, containing both β-lactamase (bla) and d-1-deoxyxylulose 5-phosphate synthase (dxs).
Development of a Real-Time Polymerase Chain Reaction Method to Measure Ligation Efficiency
An efficient method to measure ligation efficiency would be a useful tool in experiments that use the ligase enzyme. In this study, real-time polymerase chain reaction (qPCR) was used to determine whether the ligation of synthetic oligonucleotides by T4 DNA ligase had occurred.
Attempted Construction of Recombinant Vectors Designed to Study the Solubility of Overexpressed Proteinase Inhibitor 2 when Co-expressed with Thioredoxin
Overexpression of recombinant proteins in Escherichia coli can result in biologically inactive aggregates of misfolded proteins known as inclusion bodies.
Exclusion of pBR322 after co-transformation with pUC19 into Escherichia coli is mediated by the rop gene
Co-transformation of plasmids is often necessary and useful in molecular biology for purposes such as introducing multiple desirable characteristics into cells.
Building an Orthogonal Replication System for Performing Directed Evolution in Escherichia coli: A Strategic Review and a Summary of the Initial Steps in Cloning Bacteriophage T7 gp4 Primase/Helicase
Techniques for directed evolution are commonly used in industry to induce mutations in a gene of interest (GOI). Rapid mutagenesis of a GOI within a host cell can be used to expedite the process of directed evolution.
Differential Transformation Efficiencies Observed for pUC19 and pBR322 in E. coli May Be Related to Calcium Chloride Concentration
Calcium chloride is commonly included in buffers used to generate chemocompetent bacterial cells. The mechanism that underlies the uptake of exogenous DNA into bacteria is not completely understood.
Chitosan Inhibits pBR322 Transformation in Escherichia coli DH5α
The effect of chitosan, a polycationic biopolymer, during transformation in Gram-negative Escherichia coli DH5α cells was investigated in this study. Chitosan was hypothesized to enhance transformation efficiency by transient membrane permeabilization in E.
Construction of Recombinant Expression Vectors to Study the Effect of Thioredoxin on Heterologous Protein Solubility
The pET-32 vector series is designed for high-level expression of recombinant thioredoxin fusion proteins. Previous studies have shown that linkage to thioredoxin increases the yield of biologically active proteins expressed in Escherichia coli.
Increasing Overhang GC-Content Increases Sticky-End Ligation Efficiency
The ligation efficiency of sticky-ends differs between overhangs generated by different restriction enzymes. Differences between the composition of these overhangs include length and GC-content, thus indicating that these properties may play a role in ligation efficiency.