Editing Periplasm (section)

{{Short description|The region between the inner and outer membrane, or cell wall}}
The '''periplasm''' is a concentrated gel-like [[matrix (biology)|matrix]] in the space between the inner [[cytoplasm]]ic membrane and the [[bacterial outer membrane]] called the ''periplasmic space'' in [[Gram-negative]] (more accurately "diderm") [[bacterium|bacteria]]. Using [[cryo-electron microscopy]] it has been found that a much smaller periplasmic space is also present in [[Gram-positive bacteria]] (more accurately "monoderm"), between cell wall and the plasma membrane.<ref name="Matias_2005">{{cite journal | vauthors = Matias VR, Beveridge TJ | title = Cryo-electron microscopy reveals native polymeric cell wall structure in Bacillus subtilis 168 and the existence of a periplasmic space | journal = Molecular Microbiology | volume = 56 | issue = 1 | pages = 240–251 | date = April 2005 | pmid = 15773993 | doi = 10.1111/j.1365-2958.2005.04535.x | s2cid = 11013569 | doi-access = free }}</ref><ref name="Zuber_2006">{{cite journal | vauthors = Zuber B, Haenni M, Ribeiro T, Minnig K, Lopes F, Moreillon P, Dubochet J | title = Granular layer in the periplasmic space of gram-positive bacteria and fine structures of Enterococcus gallinarum and Streptococcus gordonii septa revealed by cryo-electron microscopy of vitreous sections | journal = Journal of Bacteriology | volume = 188 | issue = 18 | pages = 6652–6660 | date = September 2006 | pmid = 16952957 | pmc = 1595480 | doi = 10.1128/JB.00391-06 }}</ref> The periplasm may constitute up to 40% of the total cell volume of gram-negative bacteria, but is a much smaller percentage in gram-positive bacteria.<ref name="isbn3-540-42608-6">{{cite book | vauthors = Holst O, Seltmann G |title=The Bacterial Cell Wall |date= January 2002 |publisher=Springer |location=Berlin |isbn=3-540-42608-6 }}</ref>