Papain absorptivity

Resistance to peptidases was also reported for the octapeptoid 6.106 when incubated with papain, chymotrypsin, or thermolysin [229], However, resistance to peptidases may not be synonymous with a long half-life in vivo, since many factors beside peptidases can be expected to contribute to the elimination of peptoids. An indirect indication of this effect can be found for antimicrobial peptoids and particularly compound CHIR29498 (6.107) [232], In mice infected with Staphyllococus aureus, this peptoid was less active when injected 2 h post-infection compared to 0 h or 0.5 h. The conclusion drawn by the authors was that the compound requires optimization for improved absorption or stability within the body. 

For the SAXS studies a CBH II sample was prepared by affinity chromatography from r. reesei QM 9414 to give the enzyme in a homogeneous form 27. In SDS-PAGE the protein had a size of 58 kDa and the isoelectric point was 4.9. Glycosy-lation was estimated as 8 to 18 % 36. The molar absorptivity at 280 nm was 75 000 M xm To obtain the core protein partial proteolytic hydrolysis with papain was per-... 

Detection of the intermediate is possible if it has a spectrum sufficiently different from that of the enzyme. The cinnamoyl chymotrypsin intermediate is characterised by a UV maximum at 292 nm the acyl papain intermediate JV-benzoylaminothionacetyl papain has a UV maximum at 313 nm. The UV absorptions of the reactions catalysed by papain and chymotrypsin wax and wane in the presence of substrate giving rise to these intermediates. 

Bypassing intestinal transmembrane transporters mainly by a paracellular absorption would avoid or limit exposure of the substrate to these efflux pumps. Improved paracellular uptake can be achieved by using fatty acids, calcium chelators such as EDTA, papain, bromelain, surfactants, chitosans, polyacrylic acid or thiolated polymers. 

Tryptophan (Trp), tyrosine (Tyr), cystine (Cys), and phenylalanine (Phe) moieties play a determinant role regarding UV light-induced chemical alterations in many proteins. After the absorption of light by these moieties, in most cases mainly by Trp and Tyr, they undergo photoionization and participate in energy-and electron-transfer processes. This not only holds for structural proteins such as keratin and fibroin [11], but also for enzymes in aqueous media such as lysozyme, trypsin, papain, ribonuclease A, and insulin [7]. The photoionization of Trp and/or Tyr residues is the major initial photochemical event, which results in inactivation in the case of enzymes. A typical mechanism pertaining to Trp residues (see Scheme 8.3) commences with the absorption of a photon and the subsequent release of an electron. In aqueous media, the latter is rapidly solvated. By the release of a proton, the tryptophan cation radical Trp is converted to the tryptophan radical Trp. ... 

Recently work has been done on enzymes which contain both thiol and/or disulphide groups, including lysozyme, trypsin and papain. In each case pulse radiolysis shows an absorption at 400-430 nm assodated... 

Protease Papain Fabric Titration, water absorption assays Hydrolysis, increased hydrophilicity [53]... 

Bromelain has shown a wide variety of pharmacological effects in cliiucal, in vitro and in vivo studies. These effects include bum debridement, anti-inflammatory activity, prevention of epinephrine-induced pulmonary edema, smooth muscle relaxation, stimulation of muscle contractions, enhanced antibiotic absorption, immunomodulation, cancer prevention and remission, antitumor activity, ulcer prevention, sinusitis relief, appetite inhibition, shortening of labor, and enhanced excretion of fat. The precise nature of these effects (some of which are not produced by other proteases such as ficin, papain, and trypsin) is not clear. 

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