Pericytes are cells that reside adjacent to microvasculature and regulate vascular function. Pericytes gained great interest in the field of wound healing and regenerative medicine due to their multipotential fate and ability to enhance angiogenesis. In burn wounds, scarring and scar contractures are the major pathologic feature and cause loss of mobility. The present study investigated the influence of burn wound environment on pericytes during wound healing. Pericytes isolated from normal skin and tangentially excised burn eschar tissues were analyzed for differences in gene and protein expression using RNA-seq., immunocytochemistry, and ELISA analyses. RNA-seq identified 443 differentially expressed genes between normal- and burn eschar-derived pericytes. Whereas, comparing normal skin pericytes to normal skin fibroblasts identified 1021 distinct genes and comparing burn eschar pericytes to normal skin fibroblasts identified 2449 differential genes. Altogether, forkhead box E1 (FOXE1), a transcription factor, was identified as a unique marker for skin pericytes. Interestingly, FOXE1 levels were significantly elevated in burn eschar pericytes compared to normal. Additionally, burn wound pericytes showed increased expression of profibrotic genes periostin, fibronectin, and endosialin and a gain in contractile function, suggesting a contribution to scarring and fibrosis. Our findings suggest that the burn wound environment promotes pericytes to differentiate into a myofibroblast-like phenotype promoting scar formation and fibrosis.

Hydrocarbon fuel biofouling and biocorrosion require expensive cleanup of aviation infrastructures unless appropriate sustainment measures are applied. The identification of novel biological control agents offers promising alternatives to the current chemical biocides used in fuel sustainment. In this study, 496 microbial fuel isolates from our in-house repository were screened to identify new endogenously produced antimicrobial compounds. Using agar plug screening, liquid culture growth testing, and Jet A fuel culture assays, the two fuel-isolate strains Pseudomonas protegens #133, and Bacillus subtilis #232 demonstrated promising biocontrol activity against bacteria, yeast, and filamentous fungi. Liquid chromatography-quadrupole time of flight tandem mass spectrometry (LC-QTOF-MS/MS) of #232 culture filtrate identified several common lipopeptide antimicrobials including gageostatin C, gageopeptin B, and miscellaneous macrolactins. In contrast, LC-QTOF-MS/MS identified the siderophore pyochelin as one of the predominant compounds in #133 culture filtrate with previously demonstrated antimicrobial effect. Jet fuel microbial consortium culture testing of #133 culture filtrate including flow-cytometry live/dead cell mechanism determination demonstrated antimicrobial action against Gram-positive bacteria. The study concludes that antimicrobial compounds secreted by #133 have bactericidal effects against Gordonia sp. and cause cell death through bacterial lysis and membrane damage with potential applications in the biocidal treatment of hydrocarbon-based aviation fuels.

Hydrocarbon fuel biofouling and biocorrosion requires expensive cleanup of aviation infrastructures unless appropriate sustainment measures are applied. Alternative to current chemical biocides used in fuel sustainment, the identification of novel biological control agents offers promising alternatives. In this study, 493 microbial fuel isolates from our in-house repository were screened to identify new endogenously produced antimicrobial compounds. Using agar plug screening, liquid culture growth testing, and Jet A fuel culture assays, the two fuel isolate strains Pseudomonas protegens #133, and Bacillus subtilis # 232 demonstrated promising biocontrol activity against bacteria, yeast and filamentous fungi. Mass spectrometry analysis (LC-MS/MS) of #232 culture filtrate identified several common lipopeptide antimicrobials including gageostatin C, gageopeptin B, and miscellaneous macrolactins. In contrast, LC-MS/MS identified the siderophore pyochelin as one of the predominant compounds in #133 culture filtrate with previously demonstrated antimicrobial effect. Jet fuel microbial consortium culture testing of #133 culture filtrate including flow-cytometry live/dead cell mechanism determination demonstrated antimicrobial action against Gram-positive Gordonia sp. bacteria. The study concludes that antimicrobial compounds secreted by #133 have bactericidal effect against Gordonia sp. and cause cell death through bacterial lysis and membrane damage with potential applications in biocidal treatment of hydrocarbon-based aviation fuels.