Grass cell wall properties influence food, feed, and biofuel feedstock usage efficiency. The glucuronoarabinoxylan of grass cell walls is esterified with the phenylpropanoid-derived hydroxycinnamic acids ferulic acid (FA) and para-coumaric acid (p-CA). Feruloyl esters undergo oxidative coupling with neighboring phenylpropanoids on glucuronoarabinoxylan and lignin. Examination of rice (Oryza sativa) mutants in a grass-expanded and -diverged clade of BAHD acyl-coenzyme A-utilizing transferases identified four mutants with altered cell wall FA or p-CA contents. Here, we report on the effects of overexpressing one of these genes, OsAt10 (LOC_Os06g39390), in rice. An activation-tagged line, OsAT10-D1, shows a 60% reduction in matrix polysaccharide-bound FA and an approximately 300% increase in p-CA in young leaf tissue but no discernible phenotypic alterations in vegetative development, lignin content, or lignin composition. Two additional independent OsAt10 overexpression lines show similar changes in FA and p-CA content. Cell wall fractionation and liquid chromatography-mass spectrometry experiments isolate the cell wall alterations in the mutant to ester conjugates of a fivecarbon sugar with p-CA and FA. These results suggest that OsAT10 is a p-coumaroyl coenzyme A transferase involved in glucuronoarabinoxylan modification. Biomass from OsAT10-D1 exhibits a 20% to 40% increase in saccharification yield depending on the assay. Thus, OsAt10 is an attractive target for improving grass cell wall quality for fuel and animal feed.

Marine subsurface environments such as deep-sea sediments, house abundant and diverse microbial communities that are believed to influence large-scale geochemical processes. These processes include the biotransformation and mineralization of numerous petroleum constituents. Thus, microbial communities in the Gulf of Mexico are thought to be responsible for the intrinsic bioremediation of crude oil released by the Deepwater Horizon (DWH) oil spill. While hydrocarbon contamination is known to enrich for aerobic, oil-degrading bacteria in deep-seawater habitats, relatively little is known about the response of communities in deep-sea sediments, where low oxygen levels may hinder such a response. Here, we examined the hypothesis that increased hydrocarbon exposure results in an altered sediment microbial community structure that reflects the prospects for oil biodegradation under the prevailing conditions. We explore this hypothesis using metagenomic analysis and metabolite profiling of deep-sea sediment samples following the DWH oil spill. The presence of aerobic microbial communities and associated functional genes was consistent among all samples, whereas, a greater number of Deltaproteobacteria and anaerobic functional genes were found in sediments closest to the DWH blowout site. Metabolite profiling also revealed a greater number of putative metabolites in sediments surrounding the blowout zone relative to a background site located 127 km away. The mass spectral analysis of the putative metabolites revealed that alkylsuccinates remained below detection levels, but a homologous series of benzylsuccinates (with carbon chain lengths from 5 to 10) could be detected. Our findings suggest that increased exposure to hydrocarbons enriches for Deltaproteobacteria, which are known to be capable of anaerobic hydrocarbon metabolism. We also provide evidence for an active microbial community metabolizing aromatic hydrocarbons in deep-sea sediments of the Gulf of Mexico.

We show that thermal wave detection and analysis can be performed, in a noncontact and highly sensitive manner, through the dependence of sample optical reflectance on temperature. Applications to the study of microelectronic materials are illustrated by an example of measuring the thickness of thin metal films.

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Posaconazole is a triazole antifungal in development for the treatment of invasive fungal infections. The authors evaluated the pharmacokinetics and safety of posaconazole in healthy subjects and in those with mild (CL(CR) = 50-80 mL/min), moderate (CL(CR) = 20-49 mL/min), and severe chronic renal disease (CL(CR) <20 mL/min; receiving outpatient hemodialysis) (n = 6/group). Subjects received one 400-mg dose of posaconazole oral suspension with a standardized high-fat breakfast. For hemodialysis-dependent subjects, this dose was given on a nonhemodialysis day, and a second 400-mg dose was given 6 hours before hemodialysis. Blood samples were collected before dose and up to 120 hours postdose. For hemodialysis-dependent subjects following the second dose, additional samples (predialyzed and postdialyzed) were collected before, during, and after dialysis. There was no correlation between posaconazole pharmacokinetics and mild to moderate renal disease; the slopes of the linear regressions for creatinine clearance versus posaconazole AUC, C(max), CL/F, and t1/2 values were not significantly different from zero (P > .130). Mean CL/F values before and during hemodialysis were comparable. Furthermore, the difference in the predialyzed and postdialyzed posaconazole concentrations was only approximately 3%, supporting that posaconazole was not removed by hemodialysis. Protein binding was similar in all groups (approximately 98%) and was unaffected by hemodialysis. Posaconazole was generally well tolerated. One patient had elevated liver function test results that were not present at baseline and were thought to be possibly related to posaconazole. Results of this single-dose study indicate that dosage adjustments for patients with varying degrees of renal disease are not required.