The methyltransferase TrmA facilitates tRNA folding through interaction with its RNA-binding domain.

tRNAs are the most highly modified RNAs in all cells, and formation of 5-methyluridine (m5U) at position 54 in the T arm is a common RNA modification found in all tRNAs. The m5U modification is generated by the methyltransferase TrmA. Here, we test and prove the hypothesis that Escherichia coli TrmA has dual functions, acting both as a methyltransferase and as a tRNA chaperone.

RNA modification enzyme TruB is a tRNA chaperone.

Cellular RNAs are chemically modified by many RNA modification enzymes; however, often the functions of modifications remain unclear, such as for pseudouridine formation in the tRNA TΨC arm by the bacterial tRNA pseudouridine synthase TruB. Here we test the hypothesis that RNA modification enzymes also act as RNA chaperones. Using TruB as a model, we demonstrate that TruB folds tRNA independent of its catalytic activity, thus increasing the fraction of tRNA that can be aminoacylated.

tRNA binding, positioning, and modification by the pseudouridine synthase Pus10.

Pus10 is the most recently identified pseudouridine synthase found in archaea and higher eukaryotes. It modifies uridine 55 in the TΨC arm of tRNAs. Here, we report the first quantitative biochemical analysis of tRNA binding and pseudouridine formation by Pyrococcus furiosus Pus10.

Pre-steady-state kinetic analysis of the three Escherichia coli pseudouridine synthases TruB, TruA, and RluA reveals uniformly slow catalysis.

Pseudouridine synthases catalyze formation of the most abundant modification of functional RNAs by site-specifically isomerizing uridines to pseudouridines. While the structure and substrate specificity of these enzymes have been studied in detail, the kinetic and the catalytic mechanism of pseudouridine synthases remain unknown. Here, the first pre-steady-state kinetic analysis of three Escherichia coli pseudouridine synthases is presented.

Enumeration and strain characterization of fecal Escherichia coli associated with feeding triticale dried distillers grain with solubles in beef cattle diets.

Triticale dried distillers grain with solubles (TDDGS), a major by-product of the bioethanol industry, has potential for utilization in animal feed. This study investigated the changes in generic fecal Escherichia coli strains associated with inclusion of TDDGS in cattle diets. Within this study, a longitudinal experiment (112 days) examined the effect of step-up increasing TDDGS inclusion from control to a final diet containing 30% TDDGS among cattle (n = 4), and a short-term experiment (28 days) compared animals (n = 16) fed control, 20%, 25%, or 30% TDDGS diets.