PMC:4996381 / 24069-25443 JSONTXT

{"target":"https://pubannotation.org/docs/sourcedb/PMC/sourceid/4996381","sourcedb":"PMC","sourceid":"4996381","source_url":"https://www.ncbi.nlm.nih.gov/pmc/4996381","text":"2.2. Choice of Membrane Material\nCellulose is the most common material used to prepare peptide arrays as initially described in the 90s [4]. In order to avoid “ring spot” (or “corona”) effects, where binding occurs mainly on the rim of the SPOT and not in its center, it has been suggested to reduce peptide density starting from about 10 nmol/cm2 and optimizing further [25]. Typically, amino-PEG500-UC540 membranes optimized for use with the MultiPep system have a density of about 400 nmol/cm2, as determined by UV quantification after coupling of Fmoc-Alanine. We found that acetyl-lysine carrying peptides synthesized on these membranes tend to saturate the readout signal very quickly, suggesting that large amounts are deposited during synthesis. This proved particularly useful when probing for very weak interactions between acetyl-lysine modified peptides and bromodomains, however strong interactions or interactions that involved binding of multiple domains to one peptide resulted in rapid signal saturation and un-interpretable results. We decided to use in-house generated membranes by directly functionalizing a cellulose surface (regular Whatman™ paper) allowing more flexibility in reducing the loading of each SPOT in our arrays by using different concentrations of Fmoc-β-Alanine during the functionalization of the membrane as previously described [26].","divisions":[{"label":"Title","span":{"begin":0,"end":32}}],"tracks":[{"project":"2_test","denotations":[{"id":"27600229-10532237-69479424","span":{"begin":372,"end":374},"obj":"10532237"},{"id":"27600229-10648860-69479425","span":{"begin":1370,"end":1372},"obj":"10648860"}],"attributes":[{"subj":"27600229-10532237-69479424","pred":"source","obj":"2_test"},{"subj":"27600229-10648860-69479425","pred":"source","obj":"2_test"}]}],"config":{"attribute types":[{"pred":"source","value type":"selection","values":[{"id":"2_test","color":"#a193ec","default":true}]}]}}