Endopeptidases intracellular

The starter cells begin to die off at the end of curd manufacture (Figure 10.21) the dead cells may lyse and release their intracellular endopeptidases (Pep O, Pep F), aminopeptidases (including Pep N, Pep A, Pep C, Pep X), tripeptidases and dipeptidases (including proline-specific peptidases) which produce a range of free amino acids (Figure 10.22). About 150 peptides have... 

Caspases are a family of intracellular cysteine endopeptidases. They play a key role in inflammation and mammalian apoptosis. They are divided into two classes based on the lengths of their N-terminal prodomains. Caspases-1,-2,-4,-5,-8, and -10 have long prodomains and -3,-6,-7,-9 have short prodomains, [from Medical Dictionary Online]... 

The clostridial neurotoxins responsible for tetanus and botulism form a new group of zinc-endopeptidases endowed with peculiar properties. They are produced as inactive precursors which are activated by specific proteolysis, followed by intracellular reduction of a single di-... 

The predominant NSLAB in Cheddar and Dutch-type cheeses are meso-philic Lactobacillus, which possess a cell wall-associated and intracellular proteinases. A range of intracellular peptidases, including dipeptidases, aminopeptidases, and endopeptidases, have been identified in Lactobacillus (see reviews by Khalid and Marth 1990a Peterson and Marshall, 1990). Interestingly, carboxypeptidase activity, which has not been found in lacto-cocci, has been reported in Lactobacillus casei (El Soda et al., 1978). 

Botulism, a neuroparalytic life-threatening disease, is caused by the botulinum neurotoxin serotype A (BoNTA). Although antibodies are effective in preventing the extracellular toxin to continue the intoxication process, they have no effect on prior intoxicated neurons. Targeting the BoNTA endopeptidase (BoNTAe) could be a valid alternative, since its inhibition may potentially neutralize the intracellular BoNTA. 

Still little is known about the system of intracellular peptidases. Some studies have been made of the so-called cathepsin, which is the intracellular peptidase system of manunalian kidney and spleen. The studies of Berg-mann and his collaborators have revealed that the system contains endopeptidases, carboxypeptidases and aminopeptidases. 

The oligopeptides formed by the action of the endopeptidases are broken down into their constituent amino acids by the action of the exopeptidases. The carboxypeptidase of the pancreas splits amino acids one by one from the C-terminus so that, by the time they reach the absorbing cells of the small intestine, the dietary proteins have been converted into a mixture of amino acids and small peptides. The mucosal cells which contain both aminopeptidases and dipeptidase take up the small peptides which are then hydrolysed either within the brush border or in the layer immediately beneath it. Thus the final stages of protein digestion, like those of carbohydrates, are intracellular. Under normal circumstances no peptides pass across the mucosa to enter the bloodstream. 

Inside the neuronal cytosol, the LC acts as a Zn2+-endopeptidase against specific intracellular protein targets present either on the plasma membrane or on the synaptic vesicle, and inhibits neurotransmitter release by disabling the exocytotic docking/fusion machinery [5,6]. BoNTs catalyze proteolysis of specific proteins of the soluble NSF attachment protein receptor (SNARE) complex that have... 

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