Progress in Bacillus subtilis Spore Surface Display Technology towards Environment, Vaccine Development, and Biocatalysis

Spore surface display is the most desirable with enhanced effects, low cost, less time consuming and the most promising technology for environmental, medical, and industrial development. Spores have various applications in industry due to their ability to survive in harsh industrial processes including heat resistance, alkaline tolerance, chemical tolerance, easy recovery, and reusability. Yeast and bacteria, including gram-positive and -negative, are the most frequently used organisms for the display of various proteins (eukaryotic and prokaryotic), but unlike spores, they can rupture easily due to nutritive properties, susceptibility to heat, pH, and chemicals. Hence, spores are the best choice to avoid these problems, and they have various applications over nonspore formers due to amenability for laboratory purposes. Various strains of Clostridium and Bacillus are spore formers, but the most suitable choice for display is Bacillus subtilis because, according to the WHO, it is safe to humans and considered as &quot;GRAS&quot; (generally recognized as safe). This review focuses on the application of spore surface display towards industries, vaccine development, the environment, and peptide library construction, with cell surface display for enhanced protein expression and high enzymatic activity. Different vectors, coat proteins, and statistical analyses can be used for linker selection to obtain greater expression and high activity of the displayed protein. (C) 2017 S. Karger AG, Basel</p

Cations Optimization for Protein Enrichment in Rice Straw by Mixed Cultures of Neurospora crassa 14-8 and Candida utilis Using Response Surface Methodology

This study investigated the effect of cation optimization by mixed cultures of Neurospora crassa and Candida utilis on the true protein (TP) content. Firstly, to enhance the nutritional contents of rice straw (RS), two fermentation parameters (effect of inoculation ratio and inoculation time) were optimized. It was found that when C. utilis was inoculated 60 h later than N. crassa with the inoculation ratio of 1:5 (N. crassa to C. utilis), the maximum TP yield was obtained. In order to further optimize TP content, Plackett-Burman design (PBD) and Box-Behnken design (BBD) of response surface methodology (RSM) were adopted. The results of PBD indicated that Mn2+, Zn2+, and Cu2+ were the significant variables. The optimum values for the three cations determined by the BBD were as follows: Mn2+ 0.06 g/L, Zn2+ 0.15 g/L, and Cu2+ 0.2 g/L. After the optimization of RSM, a model was proposed to predict the optimum value 10.36% confirmed by the experimental result 9.84%. The TP content increased from 3.98 to 9.84%, with 147.24% of its increase rate. This study proposed an ecofriendly and economical way to convert RS into protein-enriched livestock feed.</p

Recurrence in unicentric castleman’s disease postoperatively: a case report and literature review

Abstract Background Our case describe a rare recurrence case of Unicentric Castleman’s disease (UCD) with hyaline vascular type 14 years after surgery. Case presentation A 35-year-old Chinese female was admitted to hospital with one and half months history chest distress and chest pain. Patient reports a history of thoracic operation for mediastinal mass 14 years ago, and it was diagnosed UCD with hyaline vascular type after postoperative pathological examination. At this time, the imaging examination showed a mediastinal mass once again. Combining the medical history, postoperative microscopically examination and immunoperoxidase staining, patient was again diagnosed UCD with hyaline vascular type again. The hyaline vascular type is the most common type and usually presents as a UCD. Most patients with UCD have no clinical symptoms. The diagnosis of UCD is generally achieved with histological and immunohidtochemical findings postoperatively. Currently, the standard treatment of UCD is the complete surgical resection, with almost no relapse postoperative. The recurrence in UCD with hyaline vascular type postoperative have not previously been reported. Therefore, herein we describe a recurrence case of UCD with hyaline vascular type 14 years after surgery. Conclusion Our case is the first case which reports the relapse of UCD with hyaline vascular type after completely surgery. It indicates that long term follow-up is necessary for patient who is diagnosed UCD after surgery

Synthesis of Highly Branched Gold Nanodendrites with a Narrow Size Distribution and Tunable NIR and SERS Using a Multiamine Surfactant

Gold nanodendrites with a long and densely branched morphology were fabricated by a seed-mediated method in a solution containing gold nanoparticles (AuNPs), bis­(amidoethyl-carbamoylethyl)­octadecylamine (C18N3), HAuCl₄, and the reducing agent ascorbic acid (AA). The length and density of the branches could be mediated by changing the AuNP seed and AA concentrations. The amphiphilic C18N3 molecules function as a template and induce the unique morphology of the AuNPs/C18N3 structures. The localized surface plasmon resonance (LSPR) peaks of the gold nanodendrites can be modulated from the visible (∼530 nm) to the near-infrared region (∼1100 nm) of the electromagnetic spectrum. Surface-enhanced Raman scattering (SERS) signals using rhodamine can also be mediated by changing the seed and AA concentrations. These unique highly branched gold nanodendrites with a narrow size distribution and tunable NIR and SERS spectra should have great potential in sensing applications

Rapid chemome profiling of Artemisia capillaris Thunb. using direct infusion-mass spectrometry

Background: As one of the most popular traditional Chinese medicines (TCMs) for the treatment of various liver diseases, virgate wormwood herb (Artemisia capillaris Thunb.) has a long application history in TCM practices. It has been well established that the chemical composition is responsible for the pronounced therapeutic spectrum of A. capillaris. Although they are comprehensive, the time-intensive liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS) assays cannot fully satisfy the analytical measurement workload from many test samples. Direct infusion-MS/MS (DI–MS/MS) may be the optimal choice to achieve high-throughput analysis if the mass spectrometer can universally record MS2 spectra. Methods: According to the application of gas phase ion fractionation concept, the MS/MSALL program enables to gain MS2 spectrum for each nominal m/z value with a data-independent acquisition algorithm via segmenting the entire MS1 ion cohort into sequential ion pieces with 1 Da width, when sufficient measurement time is allowed by DI approach. Here, rapid clarification of the chemical composition was attempted for A. capillaris using DI–MS/MSALL. A. capillaris extract was imported directly into the electrospray ionization interface to obtain the MS/MSALL measurement. After the MS1-MS2 dataset was well organized, we focused on structural characterization through retrieving information from the available databases and literature. Results: Twenty-six compounds were found, including 12 caffeoyl quinic acid derivatives, 7 flavonoids, and 7 compounds belonging to other chemical families. Among them, 24 ones were structurally identified. Compared with the LC–MS/MS technique, DI–MS/MSALL has the advantages of low-costing, solvent-saving, and time-saving. Conclusions: Chemical profiling of A. capillaris extract was accomplished within 5 min by DI–MS/MSALL, and this technique can be an alternative choice for chemical profile characterization of TCMs due to its extraordinary high-throughput advantage

Expression and Characterization of a Novel Nitrilase from Hyperthermophilic Bacterium Thermotoga maritima MSB8

The present study describes the gene cloning, overexpression and characterization of a novel nitrilase from hyperthermophilic bacterium Thermotoga maritima MSB8. The nitrilase gene consisted of 804 base pairs, encoding a protein of 268 amino acid residues with a molecular mass of 30.07 kDa after SDS-PAGE analysis. The optimal temperature and pH of the purified enzyme were 45 degrees C and 7.5, respectively. The enzyme demonstrated good temperature tolerance, with 40% residual activity after 60 min of heat treatment at 75 degrees C. The kinetic constants V-max and K-m of this nitrilase toward 3-cyanopyridine were 3.12 mu mol/min/mg and 7.63 mM, respectively. Furthermore, this novel nitrilase exhibited a broad spectrum toward the hydrolysis of the aliphatic nitriles among the tested substrates, and particularly was specific to aliphatic dinitriles like succinonitrile, which was distinguished from most nitrilases ever reported. The catalytic efficiency k(cat)/K-m was 0.44 /mM/s toward succinonitrile. This distinct characteristic might enable this nitrilase to be a potential candidate for industrial applications for biosynthesis of carboxylic acid.</p

Orlistat response to missense mutations in lipoprotein lipase

The human lipoprotein lipase (LPL) is a therapeutic target for obesity, and inhibition of LPL with the approved small molecule agent orlistat has been widely used in clinic to treat obesity-related health problems such as diabetes and cardiovascular diseases. However, a variety of missense mutations in LPL protein have been observed, which may cause resistance or sensitization for orlistat, largely limiting the clinical applications of orlistat in obesity therapy. Here, we integrated molecular dynamics simulations and enzyme inhibition to investigate orlistat response to 16 disorder-associated missense mutations in LPL catalytic domain. It was found that most mutations have a modest effect on orlistat binding, and only few can exert strong impact to the binding. Three unfavorable (Trp86Arg, Ile194Thr, and Glu242Lys) and two favorable (His136Arg and Gly188Glu) mutations were identified, which can alter the binding affinity and inhibitory activity of orlistat considerably. Structural and energetic analysis revealed that these potent mutations induce orlistat resistance and sensitization by directly influencing the intermolecular interaction between LPL and orlistat or by indirectly addressing allosteric effect on LPL structure. (C) 2016 International Union of Biochemistry and Molecular Biology, Inc.</p

Protein Production Through Microbial Conversion of Rice Straw by Multi-Strain Fermentation

Multi-strain mixed fermentation can provide a relatively complete lignocellulosic enzyme system compared with single-strain fermentation. This study was firstly to screen strains which have a strong ability to hydrolyse rice straw (RS) enzymatically and enrich true protein (TP). Then, the conditions in the process of SSF, including the optimum inoculum size of mixed strains, inoculation ratio, and different inoculation time of N. crassa 14-8, were optimized. The experimental results showed that the highest TP content could be obtained by using N. crassa 14-8, C. utilis, and P. chrysosporium as mixed strains, and 5mM Mn2+ and 50mM veratryl alcohol were used as inducers of lignin peroxidase (LiP) to improve the efficiency of enzymatic hydrolysis. When N. crassa 14-8 was inoculated 1day later than P. chrysosporium, the total inoculum size was 10%, and the optimum ratio of N. crassa 14-8 to P. chrysosporium was 1:2, the maximum TP yield (8.89%) was obtained, with 123.37% of its increase rate. This work proposed a technique with potential application in large-scale feedstuff protein conversion