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Bariatric surgery is associated with near‐immediate remission of type 2 diabetes and recently suggested as a treatment for type 2 diabetes. Specifically, Roux‐en‐Y gastric bypass has been a focus of much research, but still, the mechanisms of action are only partly elucidated. We aim to investigate whether some mechanisms might be mediated by free fatty acids (FFAs). We measured eight fractionated FFAs before and up to 2 years after Roux‐en‐Y gastric bypass surgery in 207 patients, divided into three groups. One non‐diabetic group, one diabetic group with post‐operative remission and one diabetic group with persistent diabetes after surgery. Pre‐ and postoperative levels of fractionated FFAs were compared within and between groups. The sum of the measured FFAs were lower in the group with persistent diabetes, compared to the other groups. The pre‐surgery level of linoleic acid in the group with persistent diabetes was significantly lower compared to the other two groups. The levels of fractionated FFAs decreased from pre‐surgery to three months after surgery, except for oleic acid and arachidonic acid and for Docosahexaenoic acid (DHA) in the non‐diabetic group. The FFAs with decreasing levels from pre‐surgery to three months post‐surgery are all precursors to oleic acid, arachidonic acid, and DHA, respectively, which may imply a drift, indicating that they need to be sustained at an acceptable level for optimal metabolic function. The fact that the sum of the measured FFAs is lower in the group with persistent diabetes may suggest that this group and the group with diabetes remission represent two distinct types of type 2 diabetes. It is proposed that linoleic acid could be used as a biomarker to determine the plausibility for type 2 diabetes remission after Roux‐en‐Y gastric bypass surgery. [ABSTRACT FROM AUTHOR]

The inclusion of peptoid monomers into antimicrobial peptides (AMPs) increases their proteolytic resistance, but introduces conformational flexibility (reduced hydrogen bonding ability and cis/trans isomerism). We here use NMR spectroscopy to answer how the insertion of a peptoid monomer influences the structure of a regular α‐helical AMP upon interaction with a dodecyl phosphocholine (DPC) micelle. Insertion of [(2‐methylpropyl)amino]acetic acid in maculatin‐G15 shows that the structural change and conformational flexibility depends on the site of insertion. This is governed by the micelle interaction of the amphipathic helices flanking the peptoid monomer and the side chain properties of the peptoid and its preceding residue.A high‐resolution structure of a peptoid–peptide hybrid (“peptomer”) is presented. The peptoid residue breaks the helix and displays cis/trans isomerism. Maculatin‐Nleu11 displays only the trans isomer. Maculatin‐Nleu13 displays almost equimolar amounts of cis and trans conformers. Peptide amphipathicity and peptoid hydrophobicity govern the cis/trans isomerism. [ABSTRACT FROM AUTHOR]

We present the antimicrobial and hemolytic activities of the decapeptide anoplin and 19 analogs thereof tested against methicillin-resistant Staphylococcus aureus ATCC 33591 (MRSA), Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), vancomycin-resistant Enterococcus faecium (ATCC 700221) (VRE), and Candida albicans (ATCC 200955). The anoplin analogs contain substitutions in amino acid positions 2, 3, 5, 6, 8, 9, and 10. We use these peptides to study the effect of altering the charge and hydrophobicity of anoplin on activity against red blood cells and microorganisms. We find that increasing the charge and/or hydrophobicity improves antimicrobial activity and increases hemolytic activity. For each strain tested, we identify at least six anoplin analogs with an improved therapeutic index compared with anoplin, the only exception being Enterococcus faecium, against which only few compounds are more specific than anoplin. Both 2Nal6 and Cha6 show improved therapeutic index against all strains tested. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Review: 36 refs. [ABSTRACT FROM AUTHOR]