Biliproteins are a widespread group of brilliantly coloured photoreceptors characterized by linear tetrapyrrolic chromophores, bilins, which are covalently bound to the apoproteins via relatively ...stable thioether bonds. Covalent binding stabilizes the chromoproteins and is mandatory for phycobilisome assembly; and, it is also important in biliprotein applications such as fluorescence labelling. Covalent binding has, on the other hand, also considerably hindered biliprotein research because autocatalytic chromophore additions are rare, and information on enzymatic addition by lyases was limited to a single example, an EF-type lyase attaching phycocyanobilin to cysteine-α84 of C-phycocyanin. The discovery of new activities for the latter lyases, and of new types of lyases, have reinvigorated research activities in the subject. So far, work has mainly concentrated on cyanobacterial phycobiliproteins. Methodological advances in the process, however, as well as the finding of often large numbers of homologues, opens new possibilities for research on the subsequent assembly/disassembly of the phycobilisome in cyanobacteria and red algae, on the assembly and organization of the cryptophyte light-harvesting system, on applications in basic research such as protein folding, and on the use of phycobiliproteins for labelling.
A novel method for cellulose hydrolysis catalyzed by mineral acids in the ionic liquid 1‐butyl‐3‐methylimidazolium chloride (C4mimCl) has been developed that facilitates the hydrolysis of cellulose ...with dramatically accelerated reaction rates at 100 °C under atmospheric pressure and without pretreatment.
Lignocellulosic biomass hydrolysis inevitably coproduces byproducts that may have various affects on downstream biotransformation. It is imperative to document the inhibitor tolerance ability of ...microbial strain in order to utilize biomass hydrolysate more effectively. To achieve better lipid production by
Rhodosporidium toruloides Y4, we performed fermentation experiments in the presence of some representative inhibitors. We found that acetate, 5-hydroxymethylfurfural and syringaldehyde had slightly inhibitory effects; p-hydroxybenzaldehyde and vanillin were toxic at a concentration over 10
mM; and furfural and its derivatives furfuryl alcohol and furoic acid inhibited cell growth by 45% at around 1
mM. We further demonstrated that inhibition is generally additive, although strong synergistic inhibitions were also observed. Finally, lipid production afforded good results in the presence of six inhibitors at their respective concentrations usually found in biomass hydrolysates. Fatty acid compositional profile of lipid samples indicated that those inhibitors had little effects on lipid biosynthesis. Our work will be useful for optimization of biomass hydrolysis processes and lipid production using lignocellulosic materials.
Spatial pattern information of carbon density in forest ecosystem including forest litter carbon (FLC) plays an important role in evaluating carbon sequestration potentials. The spatial variation of ...FLC density in the typical subtropical forests in southeastern China was investigated using Moran's I, geostatistics and a geographical information system (GIS). A total of 839 forest litter samples were collected based on a 12 km (south–north) × 6 km (east–west) grid system in Zhejiang province. Forest litter carbon density values were very variable, ranging from 10.2 kg ha−1 to 8841.3 kg ha−1, with an average of 1786.7 kg ha−1. The aboveground biomass had the strongest positive correlation with FLC density, followed by forest age and elevation. Global Moran's I revealed that FLC density had significant positive spatial autocorrelation. Clear spatial patterns were observed using local Moran's I. A spherical model was chosen to fit the experimental semivariogram. The moderate "nugget-to-sill" (0.536) value revealed that both natural and anthropogenic factors played a key role in spatial heterogeneity of FLC density. High FLC density values were mainly distributed in northwestern and western part of Zhejiang province, which were related to adopting long-term policy of forest conservation in these areas, while Hang-Jia-Hu (HJH) Plain, Jin-Qu (JQ) Basin and coastal areas had low FLC density due to low forest coverage and intensive management of economic forests. These spatial patterns were in line with the spatial-cluster map described by local Moran's I. Therefore, Moran's I, combined with geostatistics and GIS, could be used to study spatial patterns of environmental variables related to forest ecosystem.
ABSTRACT
The red yeast Rhodosporidium toruloides naturally produces microbial lipids and carotenoids. In the past decade or so, many studies demonstrated R. toruloides as a promising platform for ...lipid production owing to its diverse substrate appetites, robust stress resistance and other favorable features. Also, significant progresses have been made in genome sequencing, multi-omic analysis and genome-scale modeling, thus illuminating the molecular basis behind its physiology, metabolism and response to environmental stresses. At the same time, genetic parts and tools are continuously being developed to manipulate this distinctive organism. Engineered R. toruloides strains are emerging for enhanced production of conventional lipids, functional lipids as well as other interesting metabolites. This review updates those progresses and highlights future directions for advanced biotechnological applications.
A review updates research progresses on the red yeast Rhodosporidium toruloidesand highlights future engineering directions.
An efficient system for hydrolysis of lignocellulose was studied. The results obtained in hydrochloric acid/C sub(4)mimCl system were compared with those achieved in conventional enzymatic or acid ...hydrolysis processes. The pellet was collected, re-suspended in deionized water, and centrifuged. Elemental analysis was done on a Vario MICRO elemental analyzer. All the FT-IR spectra were collected on an FTIR spectrometer with a resolution of 4 cm super(-1) and 64 scans in the region of 4000-400 cm super(-1). It was demonstrated that acid on ionic liquid was an effective combination for hydrolysis of lignocellulosic materials. High total reducing sugar (TRS) yields were realized under mild conditions with reduced acid loading, usually 2-50 wt percent.
The Y-stent technique, including crossing-Y and kissing-Y, is a promising therapeutic option for some complex bifurcation aneurysms. Here, its efficacy and safety are evaluated on the basis of 11 ...bifurcation aneurysms.
A retrospective review was conducted for all patients who underwent endovascular treatment of aneurysms in our department between January 2009 and June 2011 to identify and analyze cases with bifurcation aneurysms reconstructed by using Y-stents.
Eleven patients (4 ruptured and 7 unruptured aneurysms) were identified (4 men, 7 women) with a mean age of 60.4 years. Nine aneurysms (2 AcomAs, 3 MCA-Bifs, 1 PcomA, 3 BA apexes) were treated by using the crossing-Y technique, and 2 (both BA apexes) were treated with the kissing-Y technique, achieving complete occlusion in 6 aneurysms, residual neck in 4, and partial occlusion in 1. Perioperatively, a single thromboembolic event occurred in 1 case without neurologic deficit, which required a salvaging second stent implantation. Means of 9.9 months of angiographic and 13.7 months of clinical follow-up were available. As a result, 9 (81.8) aneurysms were completely occluded, 1 with a residual neck remained stable, and 1 residual aneurysm sac was recanalized, which was retreated and achieved a complete occlusion. All patients were independent with an mRS score of 0-1 at discharge and follow-up.
In selected patients, the reconstruction of bifurcation aneurysms by using the Y-stent can be successfully achieved with satisfactory midterm results.
Nitrogen-limited conditions have been routinely prepared for efficient lipid production by oleaginous microorganisms. However, it is difficult to attain high cellular lipid contents with natural ...nitrogen-rich substrates. In the present study, we showed that lipid accumulation by Rhodosporidium toruloides Y4 was directly linked to the carbon to phosphorus (C/P) molar ratios of the culture media. Moreover, such lipid accumulation phenomena were effective regardless of the presence of high amounts of nitrogen sources. Thus, cellular lipid content and lipid yield were 62.2% and 0.205g/g glucose, respectively, using a medium with a carbon to nitrogen (C/N) molar ratio of 6.1 and a C/P molar ratio of 9552. This work suggested that phosphorus limitation can be equally effective and efficient to mediate lipid accumulation, which in turn, provides opportunities to produce microbial lipid more economically using natural or waste materials with high nitrogen content.
Self-propelling microparticles are often proposed as synthetic models for biological microswimmers, yet they lack the internally regulated adaptation of their biological counterparts. Conversely, ...adaptation can be encoded in larger-scale soft-robotic devices but remains elusive to transfer to the colloidal scale. Here, we create responsive microswimmers, powered by electro-hydrodynamic flows, which can adapt their motility via internal reconfiguration. Using sequential capillary assembly, we fabricate deterministic colloidal clusters comprising soft thermo-responsive microgels and light-absorbing particles. Light absorption induces preferential local heating and triggers the volume phase transition of the microgels, leading to an adaptation of the clusters' motility, which is orthogonal to their propulsion scheme. We rationalize this response via the coupling between self-propulsion and variations of particle shape and dielectric properties upon heating. Harnessing such coupling allows for strategies to achieve local dynamical control with simple illumination patterns, revealing exciting opportunities for developing tactic active materials.
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