Molecular cloning and sequencing showed that Mycoplasma gallisepticum, like Mycoplasma capricolum, contains both tRNAUCA and tRNACCA genes, while Mycoplasma pneumoniae and Mycoplasma genitalium each appear to have only a tRNAUCA gene. Therefore, these mycoplasma species contain a tRNA with the anticodon UCA that can translate both UGA and UGG codons.Although UGA is a stop (opal) (Fig. 1A) were employed as probes, and they gave identical results (not shown). The hybridizing DNA fragments from M. genitalium (AluI, DraI, and EcoRI fragments of 390 bp, 622 bp, and 5 kbp, respectively) and M. gallisepticum (410-and 850-bp AluI and 5.45-and 5.75-kbp EcoRI fragments) were cloned in E. coli. These regions were mapped, and relevant portions of both strands were sequenced.The cloned M. genitalium DNA was found to contain a tRNA gene with the anticodon UCA (Fig. 2B), while the M. gallisepticum clones contained both a tRNA gene with the anticodon UCA (Fig. 2C) and one with the anticodon CCA 504 on June 7, 2019 by guest

BackgroundUnder conditions of salt stress, plants respond by initiating phosphorylation cascades. Many key phosphorylation events occur at the membrane. However, to date only limited sites have been identified that are phosphorylated in response to salt stress in plants.ResultsMembrane fractions from three-day and 200 mM salt-treated Arabidopsis suspension plants were isolated, followed by protease shaving and enrichment using Zirconium ion-charged magnetic beads, and tandem mass spectrometry analyses. From this isolation, 18 phosphorylation sites from 15 Arabidopsis proteins were identified. A unique phosphorylation site in 14-3-3-interacting protein AHA1 was predominately identified in 200 mM salt-treated plants. We also identified some phosphorylation sites in aquaporins. A doubly phosphorylated peptide of PIP2;1 as well as a phosphopeptide containing a single phosphorylation site (Ser-283) and a phosphopeptide containing another site (Ser-286) of aquaporin PIP2;4 were identified respectively. These two sites appeared to be novel of which were not reported before. In addition, quantitative analyses of protein phosphorylation with either label-free or stable-isotope labeling were also employed in this study. The results indicated that level of phosphopeptides on five membrane proteins such as AHA1, STP1, Patellin-2, probable inactive receptor kinase (At3g02880), and probable purine permease 18 showed at least two-fold increase in comparison to control in response to 200 mM salt-stress.ConclusionIn this study, we successfully identified novel salt stress-responsive protein phosphorylation sites from membrane isolates of abiotic-stressed plants by membrane shaving followed by Zr4+-IMAC enrichment. The identified phosphorylation sites can be important in the salt stress response in plants.

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Biofilms are natural forms of cell immobilization in which microorganisms attach to solid supports. At ISU, we have developed plastic composite-supports (PCS) (agricultural material (soybean hulls or oat hulls), complex nutrients, and polypropylene) which stimulate biofilm formation and which supply nutrients to the attached microorganisms. Various PCS blends were initially evaluated in repeated-batch culture-tube fermentation with Saccharomyces cerevisiae (ATCC 24859) in low organic nitrogen medium. The selected PCS (40% soybean hull, 5% soybean flour, 5% yeast extract-salt and 50% polypropylene) was then used in continuous and repeated-batch fermentation in various media containing lowered nitrogen content with selected PCS. During continuous fermentation, S. cerevisiae demonstrated two to 10 times higher ethanol production in PCS bioreactors than polypropylene-alone support (PPS) control. S. cerevisiae produced 30 g L-1 ethanol on PCS with ammonium sulfate medium in repeated batch fermentation, whereas PPS-control produced 5 g L-1 ethanol. Overall, increased productivity in low cost medium can be achieved beyond conventional fermentations using this novel bioreactor design.