Raman Microspectroscopy Imaging Analysis of Extracellular Vesicles Biogenesis by Filamentous Fungus Penicilium chrysogenum

Abstract

The mechanism of production of extracellular vesicles (EVs) and their molecular contents are of great interest due to their diverse roles in biological systems and are far from being completely understood. Even though cellular cargo releases mediated by EVs have been demonstrated in several cases, their role in secondary metabolite production and release remains elusive. In this study, this aspect is investigated in detail using Raman microspectroscopic imaging. Considerable evidence is provided to suggest that the release of antibiotic penicillin by the filamentous fungus Penicillium chrysogenum involves EVs. Further, the study also reveals morphological modifications of the fungal body during biogenesis, changes in cell composition at the locus of biogenesis, and major molecular contents of the released EVs. The results suggest a possible general role of EVs in the release of antibiotics from the producing organisms.

Extracellular Vesicle Formation in Cryptococcus deuterogattii Impacts Fungal Virulence and Requires the NOP16 Gene

“…The mechanisms of biogenesis of fungal EVs are still poorly known, which impairs the design of experimental models for the study of their functions. Although much progress has been made in the identification of the protein and nucleic acid components of fungal EVs (5,(9)(10)(11)(12), their small molecule composition was only recently addressed in C. deuterogattii (13), Penicillium digitatum (14), P. chrysogenum (15), and Histoplasma capsulatum (16). In C. deuterogattii, small molecule analysis of EVs revealed the presence of a peptide controlling infection in the Galleria mellonella model (13).…”

Mycelial differentiation linked avermectin production in Streptomyces avermitilis studied with Raman imaging

“…Additionally, Raman band derived from C=C stretching vibration, which represents the degree of unsaturation of fatty acids, was observed at 1657 cm −1 . The Raman band at 1747 cm −1 indicates ester vibration (Samuel et al 2022). Component 4 shows two prominent Raman bands of avermectin at 1629 cm −1 and 1676 cm −1 assignable to conjugated (-C=C-C=C-) and non-conjugated trans C=C (Fig.…”

“…In our earlier studies, we have demonstrated application of Raman microspectroscopy in simultaneously analyzing subcellular localization of several biomolecules including secondary metabolites in Streptomyces nodosus, Penicillium chrysogenum , and Entotheonella . (Miyaoka et al 2014; Horii et al 2020; Samuel et al 2022; Kogawa et al 2022). In the present study, using Raman imaging we demonstrate presence of avermectin at specific morphologically differentiated locations of filamentous mycelia of Streptomyces avermitilis .…”