Lytic cell wall

Dunlop [18] proposed a model for sub-lytic effects in plant cells, based on the same principles, but including four properties postulated to be of particular importance in these systems, namely calcium ion flux, osmo-regulation, cell-cell contact/aggregation and stress protein expression. Of these factors, osmo-regulation (and its inter-relationship with the cell wall) and aggregation patterns, in particular, distinguish plant cells from mammalian cell systems. 

Many microorganisms produce enzymes that lyse the cell wall of yeast. The most extensive work has been done with the lytic system from Arthrobacter sp., Cytophaga sp., Oerskovia, Bacillus circulans, Rhizopus, Tri-choderma, Penicillium, Pellicularia sp., Rhizoctonia, and Streptomyces sp. (3-9). 

The lytic enzyme systems, active against yeast cell walls, usually contain l,3-/ -glucanases, proteases, mannanases, chitinases, and 1,6-) -glucanases. The proportion of those enzyme activities, their action pattern, synergism, and dependence on inhibitors constitute the activity profile... 

Bulgecins were reported for the first time in 1982 [158]. Their structures, such as (94), were established soon afterwards [159, 160] and they were found to interfere with the cell-wall synthesis of gram-negative bacteria due to a unique mechanism inhibiting vital bacterial Soluble Lytic Transglycosylase (SLT) [161]. 

Enzyme Treatment. There are a number of enzymes which hydrolyze the microbial cell wall constituents. Enzymes exhibiting these activities include lysozyme, enzyme from snail extract and lytic enzyme systems of microbial origin composed of proteases,... 

Mainly used to indicate living cells after digestion of the outer cell wall via lytic enzymes. The protoplasma of these cells is still enclosed by the undestroyed plasma-membrane. 

The only way for microbes to enter a healthy plant is via the stomata or at sites of injury, inflicted by herbivory, wind, or other accidents. At the site of wounding, plants often accumulate suberin, lignin, callose, gums, or other resinous substances which close off the respective areas (4.17). In addition, antimicrobial agents are produced such as lysozyme and chitinase, lytic enzymes stored in the vacuole which can degrade bacterial and fungal cell walls, protease inhibitors which can inhibit microbial proteases, or secondary metabolites with antimicrobial activity. 

Chemical structures of the cell wall peptidoglycans and points of attack by different lytic enzymes. 

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