China 
Africa 
Explore chapters and articles related to this topic
Biosynthesis and Genetics of Lipopolysaccharide Core
Published in Helmut Brade, Steven M. Opal, Stefanie N. Vogel, David C. Morrison, Endotoxin in Health and Disease, 2020
David E. Heinrichs, Chris Whitfield, Miguel A. Valvano
Rhamnose has been detected in the E. coli K-12 inner core region, attached to the KdoII residue as a partial substituent (66,139). The biosynthetic precursor TDP-rhamnose is encoded by the rmlABCD (formerly rfbABCD) genes located in the O-PS biosynthesis region of E. coli K-12 although enzymes for part of the TDP-rhamnose pathway are duplicated in the wec (formerly rff) (enterobacterial common antigen biosynthesis) gene cluster (140). The original O-PS (serotype 016) of E. coli K-12 contained rhamnose residues (141), but E. coli K-12 strains of the Y10 lineage harbor a mutation in the rmlD gene and are therefore unable to make TDP-rhamnose, which results in the typical R-LPS phenotype of these strains (141,142). The rmlD mutation also alters the LPS banding pattern in SDS-PAGE, and it has been proposed that this observation reflects the loss of the core OS rhamnose substituents (60,143). However, in the absence of chemical analysis of LPS, such conclusions should be viewed as tentative. The identity of the gene encoding rhamnosyl transferase activity is unknown.
Isolation and Characterization of Pregnancy-Related Proteins
Published in Gábor N. Than, Hans Bohn, Dénes G. Szabó, Advances in Pregnancy-Related Protein Research, 2020
The analysis of the carbohydrates was carried out as follows: After hydrolysis of the glycosidic bonds, the liberated neutral sugars were complexed with borate and separated by anion-exchange chromatography according to the method of Lee et al.7 Their quantitation was performed by the color reaction with copper(I)-bicinchoninat as described by Mopper and Gindler.8 Rhamnose was used as the internal standard. The aminosugars were detected and determined by their reaction with ninhydrin. The neuraminic (sialic) acid content was determined by the method of Warren.9 In earlier investigations (before 1983) the carbohydrates (hexoses, hexosamines, fucose, and sialic acid) were determined by the method described by Schultze et al.10
Champion Microalgal Forms for Food and Health Applications
Published in Gokare A. Ravishankar, Ranga Rao Ambati, Handbook of Algal Technologies and Phytochemicals, 2019
Chiara Toniolo, Marcello Nicoletti, Paola Del Serrone, Ambati Ranga Rao, Gokare A. Ravishankar
Polysaccharides are used in food industries to develop a range of products. They are also used in nutraceuticals, cosmetics, and pharmaceutical industries (Plaza et al. 2009). Polysaccharides from S. platensis and C. pyrenoidosa have shown antitumor, immunomodulatory, and antioxidant properties (Sheng et al. 2007). The polysaccharides- immulina and immurella were isolated from S. platensis and C. pyrenoidosa, respectively (Pugh et al. 2001). Rhamnose was found as the main compound in Spirulina (Lee et al. 1998). Two polysaccharides (658Da) and (406Da) that were produced by C. pyrenoidosa strains were characterized (Becker 2007).
Effects of fecal microbiota transplantation in subjects with irritable bowel syndrome are mirrored by changes in gut microbiome
Published in Gut Microbes, 2020
Rasmus Goll, Peter Holger Johnsen, Erik Hjerde, Joseph Diab, Per Christian Valle, Frank Hilpusch, Jorunn Pauline Cavanagh
The involvement of certain functional subsystems raises interesting questions about the basic pathophysiology of IBS. When we consider the role of a FODMAP-reduced diet in IBS treatment, SCFA and carbohydrate signals are of special interest. FODMAPs are a group of short-chain carbohydrates hypothesized to induce symptoms, possibly by altered colonic fermentation of these compounds, leading to a change in the functional output, which then induces gut symptoms.6,8 A recent study found reduced levels of inflammatory cytokines, an altered gut microbiota profile, and reduced levels of short-chain fatty acids to be associated with symptom relief from a low-FODMAP diet.32 Here, we can demonstrate that relative to Donor stool, the fecal samples from IBS patients have a lower representation of carbohydrate-related subsystems. In the Effect group, increases in D-Galacturonate and D-Glucuronate utilization, D-ribose utilization, L-rhamnose utilization, and Lactose and Galactose uptake and utilization were observed after 12 months. The L-rhamnose pathway was recently reported to be among the top five microbial pathways associated with 53% of fecal metabolites found in 479 unrelated individuals.31 Thus, the functional output of our FMT treatment closes the gap to the Donor profile in the Effect group. This change is not seen in the No effect group. All other subsystem clusters show a tendency of convergence toward the Donor profile in both the Effect and No effect groups.
Metabolism study of hesperetin and hesperidin in rats by UHPLC-LTQ-Orbitrap MS n
Published in Xenobiotica, 2020
Qishu Jiao, Lulu Xu, Lijuan Jiang, Yanyan Jiang, Jiayu Zhang, Bin Liu
In this work, we proposed an effective strategy for the systematic screening and identification metabolites of HPD and HPT, which was profiled using UHPLC-LTQ-Orbitrap MSn with the process of drug metabolism. First, full mass scan analysis was performed on UHPLC-LTQ-Orbitrap MS while accurate MS and MS/MS datasets were obtained by a data-dependent acquisition method. Second, the mass fragmentation pathways of both HPT and HPD were investigated and the characteristic product ions were identified to rapid screening and structural identification of metabolites. Third, metabolite templates were used to screening potential metabolites. It was reported that when HPD was consumed by rats and humans, the rhamnose part of the rutinoside group was hydrolyzed by the intestinal flora and produced HPT-7-O-glucoside and HPT (Kanaze et al., 2007; Matsumoto et al., 2004; Nielsen et al., 2006; Yamada et al., 2006). Therefore, the template of HPT was HPT (C16H14O6), and the templates of HPD were HPD (C28H34O15) and HPT-7-O-glucoside (C22H26O11), HPT (C16H14O6). Then, based on the accurate mass measurement, chromatographic retention times, fragmentation pathways of metabolites and relevant drug biotransformation knowledge, the molecular weights and the compositions of metabolites were predicted.
Alkyl rhamnosides, a series of amphiphilic materials exerting broad-spectrum anti-biofilm activity against pathogenic bacteria via multiple mechanisms
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Guanghua Peng, Xucheng Hou, Wenxi Zhang, Maoyuan Song, Mengya Yin, Jiaxing Wang, Jiajia Li, Yajie Liu, Yuanyuan Zhang, Wenkai Zhou, Xinru Li, Guiling Li
After 18 h incubation for S. aureus and 12 h incubation for P. aeruginosa at 37 °C without shaking, wells were emptied and the planktonic cells were discarded by washing the wells three times with PBS. Adhesion of cells and biofilm formation were quantified by using the crystal violet assay [16]. The adherent microorganisms were fixed with 200 μL of methanol per well, and after 15 min, the plates were emptied and left to dry. Then, the wells were stained with 200 μL of crystal violet methanol solution (0.1%, w/v) for 20 min at room temperature. Excess dye was rinsed out by placing the plate under running tap water. Subsequently, the plates were air-dried, and the dye bound to the adherent microorganisms was resolubilized with 200 μL of acetic acid in water (33%, v/v) per well. The absorbance (A) of each well was measured in a microplate reader (Multiskan Mk3, Thermo Scientific, Waltham, MA) at 560 nm using 33% (w/v) acetic acid in water as the blank. The medium without the alkyl rhamnosides was used as non-treated control. The results were expressed in terms of percentage of inhibition compared to alkyl rhamnosides-untreated wells. The percentage of inhibition at different alkyl rhamnoside concentrations for each microorganism was calculated as: