Fig. 1

BMV biogenesis and load kinds, comparing Gram-negative and positive bacteria. Researchers offered the organization of OMVs because of the agglomeration of phospholipids due to the elimination or reduced expression of vacj and yrb genes. Novel investigation proposed a novel pathway resulting in the organization of vesicles named the outer-inner membrane vesicles (OIMVs) and explosive outer-membrane vesicles (EOMVs) based on explosive cell lysis activated through the enzymatic action of endolysins [50]. Gram-negative BMVs are produced via two major models, blebbing of the OM and explosive cell lysis. The insertion of hydrophobic molecules or the inconsistency of peptidoglycan biosynthesis into the OM causes blebbing of the OM, which generates classic OMV. The weakness of the peptidoglycan layer through endolysin leads the IM to protrude into the periplasm, which develops explosive EOMV or OIMV. In addition, the biogenesis mechanism of gram-positive BMVs release is bubbling cell death. The endolysin destroys the peptidoglycan layer and leads to bubbling cell death in gram-positive bacteria, and generates CMVs. The difference in loads of gram-positive and negative BMVs goes beyond the presence of LPS and contains other molecules, including nucleic acids, proteins, lipids, and metabolites [44]