Investigation of the antimicrobial activity of soy peptides by developing a high throughput drug screening assay

BackgroundAntimicrobial resistance is a great concern in the medical community, as well as food industry. Soy peptides were tested against bacterial biofilms for their antimicrobial activity. A high throughput drug screening assay was developed using microfluidic technology, RAMAN spectroscopy, and optical microscopy for rapid screening of antimicrobials and rapid identification of pathogens.MethodsSynthesized PGTAVFK and IKAFKEATKVDKVVVLWTA soy peptides were tested against Pseudomonas aeruginosa and Listeria monocytogenes using a microdilution assay. Microfluidic technology in combination with Surface Enhanced RAMAN Spectroscopy (SERS) and optical microscopy was used for rapid screening of soy peptides, pathogen identification, and to visualize the impact of selected peptides.ResultsThe PGTAVFK peptide did not significantly affect P. aeruginosa, although it had an inhibitory effect on L. monocytogenes above a concentration of 625 µM. IKAFKEATKVDKVVVLWTA was effective against both P. aeruginosa and L. monocytogenes above a concentration of 37.2 µM. High throughput drug screening assays were able to reduce the screening and bacterial detection time to 4 h. SERS spectra was used to distinguish the two bacterial species.ConclusionsPGTAVFK and IKAFKEATKVDKVVVLWTA soy peptides showed antimicrobial activity against P. aeruginosa and L. monocytogenes. Development of high throughput assays could streamline the drug screening and bacterial detection process.General significanceThe results of this study show that the antimicrobial properties, biocompatibility, and biodegradability of soy peptides could possibly make them an alternative to the ineffective antimicrobials and antibiotics currently used in the food and medical fields. High throughput drug screening assays could help hasten pre-clinical trials in the medical field.     

Differential effector gene expression underpins epistasis in a plant fungal disease

Fungal effector–host sensitivity gene interactions play a key role in determining the outcome of septoria nodorum blotch disease (SNB) caused by Parastagonospora nodorum on wheat. The pathosystem is complex and mediated by interaction of multiple fungal necrotrophic effector–host sensitivity gene systems. Three effector sensitivity gene systems are well characterized in this pathosystem; SnToxA–Tsn1, SnTox1–Snn1 and SnTox3–Snn3. We tested a wheat mapping population that segregated for Snn1 and Snn3 with SN15, an aggressive P. nodorum isolate that produces SnToxA, SnTox1 and SnTox3, to study the inheritance of sensitivity to SnTox1 and SnTox3 and disease susceptibility. Interval quantitative trait locus (QTL) mapping showed that the SnTox1–Snn1 interaction was paramount in SNB development on both seedlings and adult plants. No effect of the SnTox3–Snn3 interaction was observed under SN15 infection. The SnTox3–Snn3 interaction was however, detected in a strain of SN15 in which SnTox1 had been deleted (tox1–6). Gene expression analysis indicates increased SnTox3 expression in tox1–6 compared with SN15. This indicates that the failure to detect the SnTox3–Snn3 interaction in SN15 is due – at least in part – to suppressed expression of SnTox3 mediated by SnTox1. Furthermore, infection of the mapping population with a strain deleted in SnToxA, SnTox1 and SnTox3 (toxa13) unmasked a significant SNB QTL on 2DS where the SnTox2 effector sensitivity gene, Snn2, is located. This QTL was not observed in SN15 and tox1–6 infections and thus suggesting that SnToxA and/or SnTox3 were epistatic. Additional QTLs responding to SNB and effectors sensitivity were detected on 2AS1 and 3AL.     

Characterization of the gene encoding 4-coumarate:CoA ligase in Coleus forskohlii

Journal of Plant Biochemistry and Biotechnology - 4-coumarate:coenzyme A ligase (4CL) converts 4-coumaric acid and its hydroxylated derivatives into the CoA thiol esters, directing carbon flux into...     

Methyl glyoxal elevation is associated with oxidative stress in rheumatoid arthritis

Methyl glyoxal (MG), a metabolic hazard plays a role in pathogenesis of different diseases. We studied the role of MG in cellular oxidative and carbonyl stress in rheumatoid arthritis (RA).

148 RA patients were divided into subgroups according to disease severity, RA factor status and age. They were acute, remission, seropositive, seronegative and JRA group. About 88 normal, young, healthy individuals were taken as control. We estimated serum level of total antioxidant status (TAS), total thiol, GSH, MG, carbonyl compounds and TBARS level of normal control and RA. The synovial fluid (SF) level of above parameters have been also evaluated in RA.

Our observation suggests that MG elevation is associated with increased level of TBARS and decreased level of GSH in all RA subgroups than normal control.

The elevation of MG along with declination of GSH and antioxidant status may be associated with free radical damage in RA.     

Use of complex media for the production of scleroglucan by Sclerotium rolfsii MTCC 2156

Submerged fermentation was carried out for the production of scleroglucan by Sclerotium rolfsii MTCC 2156 using complex media, such as coconut water, sugarcane molasses and sugarcane juice at 28+/-2 degrees C and 180 rpm for 72 h. Sugarcane juice gave maximum scleroglucan production of 23.87 g/l as compared to 12.58 and 18.45 g/l with coconut water and sugarcane molasses, respectively. Utilization of these substrates would be ecologically sound and economically advantageous.     

Interactions of human O6-alkylguanine-DNA alkyltransferase (AGT) with short single-stranded DNAs

The O6-alkylguanine-DNA alkyltransferase (AGT) repairs O6-alkylguanine and O4-alkylthymine adducts in single-stranded and duplex DNAs. Here we characterize the binding of AGT to single-stranded DNAs ranging in length from 5 to 78 nucleotides (nt). Binding is moderately cooperative (37.9 +/- 3.0 相似文献   

Internalization of beta-amyloid peptide by primary neurons in the absence of apolipoprotein E

Extracellular accumulation of beta-amyloid peptide (Abeta) has been linked to the development of Alzheimer disease. The importance of intraneuronal Abeta has been recognized more recently. Although considerable evidence indicates that extracellular Abeta contributes to the intracellular pool of Abeta, the mechanisms involved in Abeta uptake by neurons are poorly understood. We examined the molecular mechanisms involved in Abeta-(1-42) internalization by primary neurons in the absence of apolipoprotein E. We demonstrated that Abeta-(1-42) is more efficiently internalized by axons than by cell bodies of sympathetic neurons, suggesting that Abeta-(1-42) uptake might be mediated by proteins enriched in the axons. Although the acetylcholine receptor alpha7nAChR, previously suggested to be involved in Abeta internalization, is enriched in axons, our results indicate that it does not mediate Abeta-(1-42) internalization. Moreover, receptors of the low density lipoprotein receptor family are not essential for Abeta-(1-42) uptake in the absence of apolipoprotein E because receptor-associated protein had no effect on Abeta uptake. By expressing the inactive dynamin mutant dynK44A and the clathrin hub we found that Abeta-(1-42) internalization is independent of clathrin but dependent on dynamin, which suggests an endocytic pathway involving caveolae/lipid rafts. Confocal microscopy studies showing that Abeta did not co-localize with the early endosome marker EEA1 further support a clathrin-independent mechanism. The lack of co-localization of Abeta with caveolin in intracellular vesicles and the normal uptake of Abeta by neurons that do not express caveolin indicate that Abeta does not require caveolin either. Instead partial co-localization of Abeta-(1-42) with cholera toxin subunit B and sensitivity to reduction of cellular cholesterol and sphingolipid levels suggest a caveolae-independent, raft-mediated mechanism. Understanding the molecular events involved in neuronal Abeta internalization might identify potential therapeutic targets for Alzheimer disease.     

A new black fly species of the subgenus Gomphostilbia (Simulium: Simuliidae: Diptera) from India

Simulium (Gomphostilbia) agasthyamalaiense sp. nov. is described based on adults, pupae and mature larvae from a medium-flowing stream of Southern Western Ghats, India. This new species is placed in the Simulium batoense species-group of the subgenus Gomphostilbia Enderlein. This new species is characterized in the female by a scutum with three brownish-black longitudinal vittae and the hind basitarsus 5.7 times as long as wide; in the female by the large facets of upper eye with 20 vertical columns and 19 horizontal rows; in the pupa the respiratory gill with medium-long common basal stalk; and in the larva arrowhead-shaped postgenal cleft. Taxonomic notes are provided for this new species and it can be distinguished from closely related species of S. (G.) peteri. Keys are constructed to distinguish this species from ten species of the batoense species-group recorded in India.www.zoobank.org/urn:lsid:zoobank.org:pub:1D1CFEE5-A762-4F68-9EAE-9E31133146C0