Combinatorial or random methods for strain engineering have been extensively used for the improvement of multigenic phenotypes and other traits for which the underlying mechanism is not fully understood. Although the preferred method has traditionally been mutagenesis and selection, our laboratory has successfully used mutant transcription factors, which direct the RNA polymerase (RNAP) during ...

Insertional mutagenesis screens using the P[lacZ, rosy+] (PZ) transposable element have provided thousands of mutant lines for analyzing genes of varied function in the fruitfly, Drosophila melanogaster. As have been observed with other P elements, many of the PZ-induced mutations result from insertion of the P element into the promoter or 5' untranslated regions of the affected gene. We docume...

Drake, John W. (University of Illinois, Urbana). Ultraviolet mutagenesis in bacteriophage T4. I. Irradiation of extracellular phage particles. J. Bacteriol. 91:1775-1780. 1966.-Ultraviolet (UV) irradiation of extracellular T4 phage particles induces about 2 x 10(-4)r mutations per lethal hit. The mutants largely escape detection unless the irradiated phages are plated with very soft overlay aga...

The OB-fold is a diverse structure superfamily based on a beta-barrel motif that is often supplemented with additional non-conserved secondary structures. Previous deletion mutagenesis and NMR hydrogen exchange studies of three OB-fold proteins showed that the structural stabilities of sites within the conserved beta-barrels were larger than sites in non-conserved segments. In this work we exam...

macrophomina phaseolina is one of the major yield limiting factors of melons in tropical and subtropical regions. for eco-friendly and effective management of the disease, 24 gamma induced mutants from trichoderma harzianum were evaluated against three isolates of the pathogen representing three geographically different regions viz. khorasan (isolate 1), garmsar (isolate 2) and khuzestan (isola...

In recent years, expression of rabbit sarcoplasmic reticulum (SR) Ca(2+)-ATPase in heterologous systems has been a widely used strategy to study altered enzymes generated by site-directed mutagenesis. Various eukaryotic expression systems have been tested, all of them yielding comparable amounts of recombinant protein. However, the relatively low yield of recombinant protein obtained so far sug...

Gene targeting with DNA-binding molecules such as triplex-forming oligonucleotides or peptide nucleic acids can be utilized to direct mutagenesis or induce recombination site-specifically. In this chapter, several detailed protocols are described for the design and use of triplex-forming molecules to bind and mediate gene modification at specific chromosomal targets. Target site identification,...