Ration of bacterial inoculums at sub-minimal inhibitory concentrations (Figure 3d,f).Table 1. Biophysical attributes of relevant lipoYC-001 custom synthesis peptide analogs. H 55 55 53 50 48 47 24 CAC 20 five 15 1 45 14 one hundred 100 100 100 HC50 12 1 14 four 28 two one hundred one hundred one hundred one hundred MIC LB Medium three three 12.55 50 50 50 aLipopeptide Sequence C14 KKc12 K C14 OOc12 O C14 OOc10 O C14(5) OOc10 O C14(five) OOc8 O C14(5) OOc6 O OOc12 OHuman b Plasma 20 20 100 two.five 2.five 5 , Reference peptide [32], shown for comparison GNF6702 Epigenetics purposes. Grey background specifies published information; H, hydrophobicity, defined as acetonitrile required for elution in reversed phase HPLC employing a C18 column. Values were rounded to nearest entire quantity; CAC, essential aggregation concentration, determined by light scattering in PBS; HC50 , lipopeptide concentration that triggered 50 hemolysis in comparison with water (determined FOR PEER Review Pharmaceutics 2021, 13, x by measuring hemoglobin leakage immediately after three h incubation in PBS at 37 C, using 1 washed human erythrocytes); MIC, 6 of 18 minimal inhibitory concentration, determined in LB medium and in plasma, utilizing OD measurements and CFU counts, respectively; a , b , imply of 3 donors, assessed on E. coli 25922. imply of 12 GNB strains, specified in Section 2;Figure 2. Time-kill Figure two. Time-kill kinetics. The bactericidal activity of ten CC14OOc12O (orange trace) is demonstrated activity of 10 M 14 OOc12 (orange trace) is demonstrated in comparison to the untreated handle (black trace) inThe The dashed horizontal line repre- the in comparison for the untreated control (black trace) in LB. LB. dashed horizontal line represents sents of detectiondetection (log10 50 CFU/mL = 1.69). Orange asterisk denotes detectable CFU. limit the limit of (log10 50 CFU/mL = 1.69). Orange asterisk denotes lack of lack of detectable CFU.Pharmaceutics 2021, 13,Figure 2. Time-kill kinetics. The bactericidal activity of 10 M C14OOc12O (orange trace) is demonstrated in comparison for the untreated handle (black trace) in LB. The dashed horizontal line repre6 of 18 sents the limit of detection (log10 50 CFU/mL = 1.69). Orange asterisk denotes lack of detectable CFU.Figure three. Animal plasma antibacterial activities against E. coli 25922. (a) Dose-dependent reduction of colony forming Figure three. Animal plasma antibacterial activities against E. coli 25922. (a) Dose-dependent reduction of colony forming units units (CFU) as determined 24 hexposure to C14(five)OOc10O OOc10 O in human plasma (80 final plasma concentration in (CFU) as determined 24 h soon after soon after exposure to C14(five) in human plasma (80 final plasma concentration in PBS). ValPBS). Values represent the mean SDfrom threefrom 3 person plasma donors (imply inoculum was 1.six 0.eight ues represent the imply SD obtained obtained individual plasma donors (imply inoculum was 1.6 0.8 106 CFU/mL). 106 CFU/mL). (b) Time-kill kinetics determined upon E.to 0, exposure to10 M C14(five)OOc10O C14(five) OOc10 O (fromrespec(b) Time-kill kinetics determined upon E. coli exposure coli 2.five, five, and 0, two.5, five, and ten (from prime to bottom, prime to bottom,Values represent the mean SD obtained from two individual plasma samples,plasma samples, every independent tively). respectively). Values represent the mean SD obtained from two individual each subjected to two subjected to assays. Panels (c ), respectively, show the OAC’s concentration-dependent activities in plasma samples obtained from two independent assays. Panels (c ), respectively, show the OAC’s concentration-dep.