Life Sciences Commons^™

Stationary Phase Mutagenesis In Bacillus Subtilis: The Interaction Between Transcription And Error-Prone Replication In Conditions Of Stress, Mary Girard, Eduardo Robleto

Undergraduate Research Opportunities Program (UROP)

While under conditions of stress, non-dividing cells may acquire beneficial mutations. This is referred to as stationary phase mutagenesis, or adaptive mutagenesis. Previous research has shown that actively transcribed genes and those under selective pressure are prone to mutations that confer escape from non-dividing conditions. Accordingly, strains lacking transcription factors have shown a drastically lower number of mutations that confer escape while under amino acid starvation than those observed in the wildtype background. Also, error-prone DNA polymerases are known to be active in cells under stress and it has been shown that strains lacking an error-prone DNA polymerase display reduced …

The Role Of Rpoe In Stationary Phase Mutagenesis In Bacillus, Turquoise C. Alexander, Eduardo A. Robleto

Undergraduate Research Opportunities Program (UROP)

Stationary phase mutagenesis is a phenomenon whereby random mutations are generated in non-dividing cells. In order to understand how these mutations arise, we use Bacillus subtilis, a gram positive rod-shaped model organism. It is hypothesize that increased transcription promotes stationary phase mutagenesis in this organism. We therefore examined the role of rpoE, a gene that encodes RNA polymerase ! subunit and proposed to influence efficiency of transcription. To this end, we will first generate a strain bearing a deletion in the rpoE gene. In order to determine if this gene is important for mutagenesis, we will examine the accumulation of …

Dna Secondary Structures And Their Contribution To Mutagenesis In B. Subtilis Stationary Phase Cells, Carmen Vallin, Katherine Ona, Chris Ross, Ronald E. Yasbin, Eduardo A. Robleto

Undergraduate Research Opportunities Program (UROP)

It is widely known and accepted that the cause of many mutations in cells are generated during the replication process of actively dividing cells, however more recent research has shown that mutations also arise in non growing conditions, a phenomenon known stationary phase mutagenesis. Much of what is known come from studies in eukaryotic and bacterial models. It is proposed that in nongrowing cells, the process of transcription plays an important role in mutagenesis. I will test the hypothesis that secondary structures formed of DNA generated transcription promote mutagenesis. The sequences transcriptiongenerated structures are speculated to be prone to mutations …

Structural Basis Of Error-Prone Replication And Stalling At A Thymine Base By Human Dna Polymerase Iota, Kevin N. Kirouac, Hong Ling

Biochemistry Publications

Human DNA polymerase iota (pol iota) is a unique member of Y-family polymerases, which preferentially misincorporates nucleotides opposite thymines (T) and halts replication at T bases. The structural basis of the high error rates remains elusive. We present three crystal structures of pol complexed with DNA containing a thymine base, paired with correct or incorrect incoming nucleotides. A narrowed active site supports a pyrimidine to pyrimidine mismatch and excludes Watson-Crick base pairing by pol. The template thymine remains in an anti conformation irrespective of incoming nucleotides. Incoming ddATP adopts a syn conformation with reduced base stacking, whereas incorrect dGTP and …

From Gene Mutation To Protein Characterization, David A. Moffet

Chemistry and Biochemistry Faculty Works

A seven-week “gene to protein” laboratory sequence is described for an undergraduate biochemistry laboratory course. Student pairs were given the task of introducing a point mutation of their choosing into the well studied protein, enhanced green fluorescent protein (EGFP). After conducting literature searches, each student group chose the mutation they wanted to introduce into EGFP. Students designed their sequence-specific mutagenic primers and constructed their desired mutation. The resulting EGFP mutant proteins were expressed in E. coli, purified and characterized. This laboratory sequence connected the major concepts of molecular biology and biochemistry, while incorporating the thrill of novel discovery in …

Crop Updates 2009 - Weeds, Catherine Borger, Abul Hashem, Mike Clarke, Aik Cheam, Harmohinder Dhammu, Vince Lambert, Chris Roberts, Russell Quartermaine, David Nicholson, Mike Jackson, Bill Campbell, John Moore, Mario D'Antuono, Paul Matson, Peter Newman, Sally Peltzer, Dave Minkey, Stephen B. Powels, Qin Yu, Mechelle Owen, Roberto Busi, Sudheesh Manalil, Leigh Smith, Peter White, Fiona Evans, Pippa Michael, Siew Lee, Rob Grima, Glenn Adam, Trevor Bell, Steve Davies, Glen Riethmuller

Crop Updates

This session covers twenty three papers from different authors:

Herbicides

1. New pre-seeding grass selective herbicides – How well do they work in zero or no-till systems? Dr Catherine Borgerand Dr Abul Hashem, Department of Agriculture and Food

2. Velocity®—An alternate mode of action for the control of wild radish in cereals, Mike Clarke, Bayer Cropscience Pty Ltd, Dr Aik Cheam, Department of Agriculture and Food, Dr Michael Walsh, WAHRI, University of Western Australia

3. Herbicide tolerance of new barley varieties, Harmohinder Dhammu, Vince Lambert, Chris Roberts and Russell Quartermaine, Department of Agriculture and Food

4. Herbicide tolerance of …

Crop Updates 2009 - Weeds, Catherine Borger, Abul Hashem, Mike Clarke, Aik Cheam, Michael Walsh, Harmohinder Dhammu, Vince Lambert, Chris Roberts, Russell Quartermaine, David Nicholson, Mike Jackson, Bill Campbell, John Moore, Mario D'Antuono, Paul Matson, Peter Newman, Sally Peltzer, Dave Minkey, Stephen B. Powles, Qin Yu, Mechelle Owen, Roberto Busi, Sudheesh Manalil, Leigh Smith, Peter White, Fiona Evans, Art Diggle, Catherine Borger, Pippa Michael, Siew Lee, Rob Grima, Glenn Adam, Trevor Bell, Steve Davies, Glen Riethmuller

Crop Updates

This session covers twenty three papers from different authors:

Herbicides

1. New pre-seeding grass selective herbicides – How well do they work in zero or no-till systems? Dr Catherine Borgerand Dr Abul Hashem, Department of Agriculture and Food

2. Velocity®—An alternate mode of action for the control of wild radish in cereals, Mike Clarke, Bayer Cropscience Pty Ltd, Dr Aik Cheam, Department of Agriculture and Food, Dr Michael Walsh, WAHRI, University of Western Australia

3. Herbicide tolerance of new barley varieties, Harmohinder Dhammu, Vince Lambert, Chris Roberts and Russell Quartermaine, Department of Agriculture and Food

4. Herbicide tolerance of …