Chymotrypsin

Department of Biochemistry, Eotvos Lorand University, and 2Biotechnology Research Group of the Hungarian Academy of Sciences, ´ ´ ´ ´ Pazmany setany 1/C, Budapest, Hungary The molecular mechanism of the autolysis of rat a-chymotrypsin B was investigated. In addition to the two already known autolytic sites, Tyr146 and Asn147, a new site formed by Phe114 was identified. The former two sites and the latter one are located in the autolysis and the interdomain loops, respectivel

9p system191 01-06-2013 36 4   Download

Duodenase is a 29-kDa serine endopeptidase that displays selective trypsin- and chymotrypsin-like substrate specificity. This enzyme has been localized to epitheliocytes of Brunner’s glands, and as described here, to mast cells within the intestinal mucosa and lungworm-infected lung, implying an important additional role in inflammation and tissue remodelling. In primary cultures of pulmonary artery fibroblasts, duodenase induced a concentration-dependent increase in [3H]thymidine incorporation with a maximal effect observed at 30 nM.

10p research12 01-06-2013 54 3   Download

Bovineb-lactoglobulin was hydrolyzed with trypsin or chymotrypsin in the course of heat treatment at 55, 60 and 65°C at neutral pH. At these temperaturesb-lactoglobulin undergoes signi®cant but reversible structural changes. In the conditions used in the present study,b-lactoglobulinwas virtually insensitive to proteolysis by either enzyme at room temperature, but underwent extensive proteolysis when either proteasewas present during the heat treatment.

11p research12 29-04-2013 33 3   Download

Achromobacterprotease I (API) has a unique region of aromatic ring stacking with Trp169–His210in close proxi-mity to the catalytic triad. This paper reveals the electrostatic role of aromatic stacking in the shift in optimum pH to the alkaline region, which is the highest pH range (8.5–10) among chymotrypsin-type serine proteases. The pH-activity profile of API showed a sigmoidal distribution that appears at pH 8–10, with a shoulder at pH 6–8.

7p research12 23-04-2013 41 2   Download

The solution structure of three small serine proteinase inhibitors, two natural and one engineered protein, SGCI (Schistocerca gregaria chymotrypsin inhibitor), SGCI[L30R, K31M] and SGTI (Schistocerca gregaria trypsin inhibitor), were determined by homonuclear NMR-spectroscopy. The molecules exhibit di€erent speci®cities towards target proteinases, where SGCI is a good chymo-trypsin inhibitor, itsmutant is apotent trypsin inhibitor, and SGTI inhibits both proteinases weakly.

11p research12 23-04-2013 33 2   Download

Although thea-chymasesof primates anddogs areknownas chymotrypsin-like proteases, the enzymatic properties of rodent a-chymases (rat mast cell protease 5/rMCP-5 and mouse mast cell protease 5/mMCP-5) have not been fully understood. We report that recombinant rMCP-5 and mMCP-5 are elastase-like proteases, not chymotrypsin-like proteases. An enzyme assay using chromogenic peptidyl substrates showed that mast cell protease-5s (MCP-5s) have a clear preference for small aliphatic amino acids (e.g. alanine, isoleucine, valine) in the P1 site of substrates....

10p tumor12 22-04-2013 36 2   Download

Butyrylcholinesterase is a serine esterase, closely related to acetylcholinesterase. Both enzymes employ a catalytic triad mechanism for catalysis, similar to that used by serine pro-teases such as a-chymotrypsin. Enzymes of this type are generally considered to be inactive at pH values below 5, because the histidine member of the catalytic triad becomes protonated. We have found that butyrylcholinesterase retains activity at pH £ 5, under conditions of excess substrate activation.

10p tumor12 20-04-2013 25 4   Download

Chymotrypsin is a prominent member of the family of serine proteases. The present studies demonstrate the presence of a native fragment contain-ing 14 residues from Ile16 to Trp29 in a-chymotrypsin that binds to chy-motrypsin at the active site with an exceptionally high affinity of 2.7 ± 0.3·10 )11 mand thus works as a highly potent competitive inhib-itor. The commercially available a-chymotrypsin was processed through a three phase partitioning system (TPP). The treated enzyme showed consid-erably enhanced activity. ...

11p awards 05-04-2013 48 3   Download

Complexation of the small serine protease inhibitorSchistocerca gregaria chymotrypsin inhibitor (SGCI), a member of the pacifastin inhibitor family, with bovine chymotrypsin was followed by NMR spectroscopy. 1 H– 15 N correlation (HSQC) spectra of the inhibitor with increasing amounts of the enzyme reveal tight and specific binding in agreement with biochemical data.

12p inspiron33 26-03-2013 47 6   Download

The 3C-like protease of the severe acute respiratory syndrome (SARS) cor-onavirus has a C-terminal extra domain in addition to the chymotrypsin-fold adopted by piconavirus 3C proteases hosting the complete catalytic machinery. Previously we identified the extra domain to be involved in enzyme dimerization which has been considered essential for the catalytic activity.

11p inspiron33 26-03-2013 41 4   Download

Although the chemical nature of the catalytic mechanism of the serine pro-tease a-chymotrypsin (a-CT) is largely understood, the influence of the enzyme’s structural dynamics on its catalysis remains uncertain. Here we investigate whether a-CT’s structural dynamics directly influence the kinet-ics of enzyme catalysis.

17p inspiron33 23-03-2013 31 3   Download

The yeast 20S proteasome is subject to sulfhydryl redox alterations, such as the oxidation of cysteine residues (Cys-SH) into cysteine sulfenic acid (Cys-SOH), followed by S-glutathionylation (Cys-S-SG). Proteasome S-glutath-ionylation promotes partial loss of chymotrypsin-like activity and post-acidic cleavage without alteration of the trypsin-like proteasomal activity.

14p galaxyss3 07-03-2013 36 5   Download

Chymases are chymotrypsin-like serine proteases that are found in large amounts in mast cell granules. So far, the extended cleavage specificities of eight such chymases have been determined, and four of these were shown to have a strong preference for acidic amino acids at position P2¢. These enzymes have basic amino acids in positions 143 and 192 (Arg and Lys, respectively).

13p mobifone23 21-01-2013 47 5   Download

Cathepsin G (CG) (EC 3.4.21.20) and chymase (EC 3.4.21.39) are two clo-sely-related chymotrypsin-like proteases that are released from cytoplasmic granules of activated mast cells and⁄or neutrophils. We investigated the potential for their substrate-binding subsites to discriminate between their substrate specificities, aiming to better understand their respective role dur-ing the progression of inflammatory diseases.

12p cosis54 04-01-2013 31 4   Download

Human chymotrypsin C (CTRC) plays a protective role in the pancreas by mitigating premature trypsinogen activation through degradation. Mutations that abolish activity or secretion of CTRC increase the risk for chronic pancreatitis.

13p cosis54 09-12-2012 40 2   Download

Potato tuber storage proteins were obtained from vacuoles isolated from field-grown starch potato tubers cv. Kuras. Vacuole sap proteins fraction-ated by gel filtration were studied by mass spectrometric analyses of trypsin and chymotrypsin digestions.

18p cosis54 09-12-2012 42 3   Download

Enzyme Nomenclature and Classification • Enzymes are commonly named by adding a suffix "-ase" to the root name of the substrate molecule it is acting upon.  For example, Lipase catalyzes the hydrolysis of a lipid triglyceride. Sucrase catalyzes

9p zingzing09 15-11-2012 65 3   Download

Trong thời gian cơ chế tác dụng của enzyme chưa được nêu ra, người ta đã đặt cho một số enzyme những tên riêng biệt như pepsine, trypsine, chymotrypsine, papaine, bromeline, …

3p pencil_7 12-10-2011 609 29   Download

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học General Psychiatry cung cấp cho các bạn kiến thức về ngành y đề tài: Lymphocyte Responses to Chymotrypsin- or Trypsin VDigested b-Lactoglobulin in Patients with Cow’s Milk Allergy...

9p thulanh10 09-10-2011 53 5   Download

Tuyển tập các báo cáo nghiên cứu khoa học của trường đại học cần thơ trên tạp chí nghiên cứu khoa học đề tài: ẢNH HƯỞNG CỦA THỨC ĂN KHÁC NHAU LÊN HOẠT TÍNH CỦA MEN TRYPSIN VÀ CHYMOTRYPSIN Ở CÁ BỐNG TƯỢNG BỘT (Oxyeleotris marmoratus)...

7p phalinh18 19-08-2011 127 14   Download