Laboratory Investigation (2012) 92, 1503-1514; doi:10.1038/labinvest.2012.114; published online 13 August 2012″
“Protein adsorption on a surface plays an important role in biomaterial science and medicine. It is strongly related to the interaction between the protein residues and the surface. Here we report all-atom molecular dynamics simulations of the adsorption of an ionic complementary peptide, EAK16-II,
to the hydrophobic highly ordered pyrolytic graphite surface. We find that, the hydrophobic interaction is the main force to govern the adsorption, and the peptide interchain electrostatic interaction affects the adsorption rate. Under neutral pH condition, the interchain electrostatic attraction facilitates the adsorption, learn more whereas under acidic and basic conditions, because of the protonation and deprotonation of glutamic acid and lysine residues,
respectively, the resulting electrostatic repulsion slows down the adsorption. We also found that under basic condition, during the adsorption peptide Chain II will be up against a choice to adsorb to the surface through the hydrophobic interaction or to form a temporary hydrophobic core with the deposited peptide Chain I. These results provide a basis for understanding some of the fundamental interactions governing peptide adsorption on the surface, which can shed new light on novel applications, such as the design of implant devices and drug delivery materials.”
“Aims: To evaluate the potential use of MALDI-TOF MS for fast and reliable selleck kinase inhibitor classification and identification of lactic acid bacteria (LAB) from traditional fermented foods. Methods and Results: A total of 119 strains of LAB from fermented meat (nem chua) were analysed with both (GTG)5-PCR fingerprinting and MALDI-TOF MS. Cluster analysis of the profiles revealed five species represented by
a single isolate both in (GTG)5-PCR and selleck chemicals llc in MALDI-TOF MS; five species grouped alike for (GTG)5-PCR and for MALDI-TOF MS; however, differences in minimal similarity between the delineated (GTG)5-PCR and MALDI-TOF MS clusters could be observed; three species showed more heterogeneity in their MALDI-TOF MS profiles compared to their (GTG)5-PCR profiles; two species, each represented by a single MALDI-TOF cluster, were subdivided in the corresponding (GTG)5-PCR dendrogram. As proof of the identification potential of MALDI-TOF MS, LAB diversity from one fermented mustard sample was analysed using MALDI- TOF MS. PheS gene sequencing was used for validation. Conclusions: MALDI-TOF MS is a powerful, fast, reliable and cost-effective technique for the identification of LAB associated with the production of fermented foods. Significance and Impact of the Study: Food LAB can be identified using MALDI-TOF MS, and its application could possibly be extended to other food matrices and/or other food-derived micro-organisms.