D.A. Malyshev, K. Dhami, H.T. Quach, T. Lavergne, P. Ordoukhanian, A. Torkamani, F.E. Romesberg, Proc. Natl. Acad. Sci. USA (2012) 109:12005-12010.
We examine the PCR amplification of DNA containing one or more d5SICS-dNaM pairs and demonstrate that this DNA may be amplified with high efficiency and with greater than 99.9% fidelity. The results demonstrate that for PCR and PCR-based applications, d5SICS-ddNaM is functionally equivalent to a natural base pair, and when combined with dA-dT and dG-dC, provides the first fully functional six-letter genetic alphabet. Read more in Nature and Biotechniques.
P.A. Smith, F.E. Romesberg, Antimicrob. Agents Chemother. (2012) 56:5054-5060.
We examine arylomycin activity as a function of concentration, bacterial cell density, target expression levels, and bacterial growth phase. We find that the activity of the arylomycins results from an insufficient flux of proteins through the secretion pathway and the resulting mislocalization of proteins. We also demonstrate that SPase inhibition results in synergistic sensitivity when combined with an aminoglycoside.
R. Adhikary, W. Yu, M. Oda, J. Zimmermann, F.E. Romesberg, J. Biol. Chem. (2012) 287:27139-27147.
We report the sequence, thermodynamic, and time-resolved spectroscopic characterization of a panel of eight antibodies (Abs) elicited to a chromophoric antigen (MPTS). Three of the Abs arose from unique germline Abs, while the remaining five comprise two sets of siblings that arose by somatic mutation of a common precursor. By characterizing both flexibility and conformational heterogeneity, we show that point mutations are capable of fixing significant differences in protein dynamics.
D. Quinto-Alemany, A. Canerina-Amaro, L.G. Hernández-Abad, F. Machín, F.E. Romesberg, C. Gil-Lamaignere, PLoS ONE (2012) 7:e42279.
Stressful lifestyle associated mutation (SLAM) assays are used to demonstrate that both S. cerevisiae and C. albicans undergo mutations to acquire resistance to the antifungal agents 5-fluorocytosine and caspofungin. Examination of the mutation spectrum shows that these aquired mutations are different from those that the occur spontaneously, in the absence of antifungal treatment. Overall, the work present a much needed model system for studying adaptive mutagenesis in eukaryotes.
K. Betz, D.A. Malyshev, T. Lavergne, W. Welte, K. Diederichs, T.J. Dwyer, P. Ordoukhanian, F.E. Romesberg, A. Marx, Nat. Chem. Biol. (2012) 8:612-614.
We report crystal structures of KlenTaq DNA polymerase at different stages of replicating dNaM-d5SICS, and show that efficient replication results from the polymerase itself inducing the required natural-like structure. Read more in Live Science.
W. Yu, P. Dawson, J. Zimmermann, F.E. Romesberg, J. Phys. Chem. B (2012) 116:6397-6403.
We report a residue-specific characterization of the thermal unfolding mechanism of cyt c using C-D bonds site-specifically incorporated at residues dispersed throughout three different structural elements within the protein. Elucidation of the detailed unfolding mechanism and the structure of the associated molten globule, both of which represent challenges to conventional techniques, are highlights of the utility of the C-D technique.
Y.X. Tan, F.E. Romesberg, MedChemComm (2012) 3:916-925.
We review the arylomycin family of natural product antibiotics, highlighting how their characterization has provided new insight into how antibiotics evolve in nature.