scholarly journals Insight into the Effects of Sous Vide on Cathepsin B and L Activities, Protein Degradation and the Ultrastructure of Beef

Foods ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 1441
Author(s):  
Yantao Yin ◽  
Jailson Pereira ◽  
Lei Zhou ◽  
Jose M. Lorenzo ◽  
Xiaona Tian ◽  
...  
Keyword(s):  
Cathepsin B ◽  
Sarcomere Length ◽  
Cathepsin L ◽  
Myofibrillar Protein ◽  
Potential Mechanism ◽  
Beef Tenderness ◽  
Fragmentation Index ◽  
Sous Vide ◽  
Hydrolysis Of ◽  
Insight Into

This study aimed to evaluate the effects of sous vide cooking (SV) on beef tenderness and its underlying potential mechanism. Beef semimembranosus (SM) were subjected to SV treatments at 45 °C, 55 °C and 65 °C for 4 h. Compared with control samples (CK, cooked at 75 °C until a core temperature of 72 °C was attained), SV treatment significantly promoted the release of cathepsin B and cathepsin L from lysosomes and decreased the shear force of beef SM (p < 0.05). In comparison with CK, samples treated with SV had more hydrolysis of myosin heavy chain and obtained higher myofibrillar fragmentation index, collagen solubility as well as longer sarcomere length (p < 0.05). The current study showed that the proteolysis of myofibrillar protein and collagen induced by cathepsin B and cathepsin L, and the limited longitudinal shrinkage together contributed to the improvement of beef tenderness upon SV.

scholarly journals Effect of Ultimate pH on Postmortem Myofibrillar Protein Degradation and Meat Quality Characteristics of Chinese Yellow Crossbreed Cattle

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Peng Li ◽  
Tiantian Wang ◽  
Yanwei Mao ◽  
Yimin Zhang ◽  
Lebao Niu ◽  
...  
Keyword(s):  
Enzymatic Activity ◽  
Protein Degradation ◽  
Meat Quality ◽  
Troponin T ◽  
Quality Characteristics ◽  
Myofibrillar Protein ◽  
Cooking Loss ◽  
Crossbred Cattle ◽  
Beef Tenderness ◽  
Fragmentation Index

This paper describes the complex effects of postmortem ultimate pH (pHu) on Chinese Yellow crossbreed cattle quality during postmortem ageing and provides an explanation of how pHu affects beef tenderness. High pHu beef had the highest initial tenderness (P<0.05) compared with other groups at 1 day postmortem. Intermediate and low pHu beef had similar initial WBSF at 1 day postmortem, but intermediate pHu beef had slower tenderization rate than low pHu beef (P<0.05). Purge loss, cooking loss,L*,a*, andb*values decreased with increasing pHu during ageing (P<0.05). Myofibril fragmentation index (MFI) was higher in high pHu beef than intermediate and low pHu beef throughout ageing (P<0.05). Protein degradation studies found that desmin and troponin-T appeared degraded within 0.5 h postmortem for high and low pHu beef, compared to >2 days for intermediate pHu beef. Overall, Chinese Yellow crossbred cattle tenderness is related to pHu, which may be affected by proteolytic enzymatic activity. Therefore, pHu may be used to predict beef tenderness and other quality characteristics during postmortem ageing. To achieve consistent tenderness, different ageing times should be used, depending on pHu.

scholarly journals Human kidney cathepsins B and L. Characterization and potential role in degradation of glomerular basement membrane

1988 ◽  
Vol 252 (1) ◽  
pp. 301-304 ◽  
Author(s):  
W H Baricos ◽  
Y Zhou ◽  
R W Mason ◽  
A J Barrett
Keyword(s):  
Basement Membrane ◽  
Glomerular Basement Membrane ◽  
Cathepsin B ◽  
Cathepsin L ◽  
Polyacrylamide Gel Electrophoresis ◽  
Human Kidney ◽  
Ph Optimum ◽  
Dose Dependent ◽  
Hydrolysis Of

Cathepsins B and L were purified from human kidney. SDS/polyacrylamide-gel electrophoresis demonstrated that cathepsins B and L, Mr 27000-30000, consist of disulphide-linked dimers, subunit Mr values 22000-25000 and 5000-7000. The pH optimum for the hydrolysis of methylcoumarylamide (-NHMec) substrates (see below) is approx. 6.0 for each enzyme. Km and kcat. are 252 microM and 364s-1 and 2.2 microM and 25.8 s-1 for the hydrolysis of Z-Phe-Arg-NHMec (where Z- represents benzyloxycarbonyl-) by cathepsins B and L respectively, and 184 microM and 158 s-1 for the hydrolysis of Z-Arg-Arg-NHMec by cathepsin B. A 10 min preincubation of cathepsin B (40 degrees C) or cathepsin L (30 degrees C) with E-64 (2.5 microM) results in complete inhibition. Under identical conditions Z-Phe-Phe-CHN2 (0.56 microM) completely inhibits cathepsin L but has little effect on cathepsin B. Incubation of glomerular basement membrane (GBM) with purified human kidney cathepsin L resulted in dose-dependent (10-40 nM) GBM degradation. In contrast, little degradation of GBM (less than 4.0%) was observed with cathepsin B. The pH optimum for GBM degradation by cathepsin L was 3.5. Cathepsin L was significantly more active in degrading GBM than was pancreatic elastase, trypsin or bacterial collagenase. These data suggest that cathepsin L may participate in the lysosomal degradation of GBM associated with normal GBM turnover in vivo.

scholarly journals Elastinolytic activity of human cathepsin L

1986 ◽  
Vol 233 (3) ◽  
pp. 925-927 ◽  
Author(s):  
R W Mason ◽  
D A Johnson ◽  
A J Barrett ◽  
H A Chapman
Keyword(s):  
Cathepsin B ◽  
Specific Activity ◽  
Cathepsin L ◽  
Cysteine Proteinases ◽  
Pancreatic Elastase ◽  
Optimum Ph ◽  
Human Cathepsin ◽  
Hydrolysis Of

The hydrolysis of a tritiated elastin substrate by the human cysteine proteinases cathepsins B and L has been studied. Cathepsin L was found to be at least 100-fold more active on this substrate than cathepsin B. The specific activity of cathepsin L at pH 5.5 for hydrolysis of elastin was about the same as that of pig pancreatic elastase at its optimum pH of 8.8.

Inhibitory effect of microwave heating on cathepsin l-induced degradation of myofibrillar protein gel

2021 ◽  
Vol 357 ◽  
pp. 129745
Author(s):  
Qian Wang ◽  
Xidong Jiao ◽  
Bowen Yan ◽  
Linglu Meng ◽  
Hongwei Cao ◽  
...  
Keyword(s):  
Microwave Heating ◽  
Cathepsin L ◽  
Inhibitory Effect ◽  
Myofibrillar Protein ◽  
Protein Gel

scholarly journals Cold-Active β-Galactosidases: Insight into Cold Adaption Mechanisms and Biotechnological Exploitation

Marine Drugs ◽  
2021 ◽  
Vol 19 (1) ◽  
pp. 43
Author(s):  
Marco Mangiagalli ◽  
Marina Lotti
Keyword(s):  
Low Temperature ◽  
Molecular Mechanisms ◽  
Building Blocks ◽  
Cold Active ◽  
Cold Adaption ◽  
Glycosyl Donor ◽  
Pharmaceutical Industries ◽  
Biotechnological Processes ◽  
Hydrolysis Of ◽  
Insight Into

β-galactosidases (EC 3.2.1.23) catalyze the hydrolysis of β-galactosidic bonds in oligosaccharides and, under certain conditions, transfer a sugar moiety from a glycosyl donor to an acceptor. Cold-active β-galactosidases are identified in microorganisms endemic to permanently low-temperature environments. While mesophilic β-galactosidases are broadly studied and employed for biotechnological purposes, the cold-active enzymes are still scarcely explored, although they may prove very useful in biotechnological processes at low temperature. This review covers several issues related to cold-active β-galactosidases, including their classification, structure and molecular mechanisms of cold adaptation. Moreover, their applications are discussed, focusing on the production of lactose-free dairy products as well as on the valorization of cheese whey and the synthesis of glycosyl building blocks for the food, cosmetic and pharmaceutical industries.

The cysteine proteinases of Schistosoma mansoni cercariae

Parasitology ◽  
1997 ◽  
Vol 114 (2) ◽  
pp. 105-112 ◽  
Author(s):  
J. P. DALTON ◽  
K. A. CLOUGH ◽  
M. K. JONES ◽  
P. J. BRINDLEY
Keyword(s):  
Schistosoma Mansoni ◽  
Cathepsin B ◽  
Cathepsin L ◽  
Serine Proteinase ◽  
Skin Penetration ◽  
Scanning Electron Micrographs ◽  
Cysteine Proteinases ◽  
Similar Function ◽  
Substrate Preferences ◽  
Serine Proteinase Activity

Based on substrate preferences, cercariae of Schistosoma mansoni were seen to express both cathepsin L and cathepsin B cysteine proteinases, although the former activity was many -fold greater. Two cathepsin L activities identified in cercarial extracts by zymography co-migrated with activities in extracts of 3 h and 24 h schisotosomula and in extracts of adult worms. Since these enzymes have been implicated in haemoglob in digestion by adult worms, they may perform a similar function in schistosomula. Immunolocalization using scanning electron micrographs showed that cathepsin L and cathepsin B proteinases were present in the cercarial post-acetabular glands. In addition, cercarial serine proteinase activities considered to facilitate skin penetration efficiently cleaved the substrates Z-Gly-Pro-Arg-NHMec and Z-Gly-Pro-Lys-NHMec. Cercariae release most of this serine proteinase activity when induced to secrete the contents of their acetabular glands. In contrast, newly transformed 3 h and 24 h schistosomula did not express this activity.

Elevations of cathepsin B and cathepsin L activities in forelimb and hind limb muscles of genetically dystrophic mice

1986 ◽  
Vol 93 (3) ◽  
pp. 642-646 ◽  
Author(s):  
Keiji Komatsu ◽  
Kazutomo Tsukuda ◽  
Jun Hosoya ◽  
Susumu Satoh
Keyword(s):  
Cathepsin B ◽  
Hind Limb ◽  
Cathepsin L ◽  
Limb Muscles ◽  
Dystrophic Mice

The crystal structure of human mitochondrial 3-ketoacyl-CoA thiolase (T1): insight into the reaction mechanism of its thiolase and thioesterase activities

2014 ◽  
Vol 70 (12) ◽  
pp. 3212-3225 ◽  
Author(s):  
Tiila-Riikka Kiema ◽  
Rajesh K. Harijan ◽  
Malgorzata Strozyk ◽  
Toshiyuki Fukao ◽  
Stefan E. H. Alexson ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Reaction Mechanism ◽  
Active Site ◽  
Quaternary Structure ◽  
Fatty Acyl ◽  
Physiological Importance ◽  
Loop Domain ◽  
Solution Studies ◽  
Hydrolysis Of ◽  
Insight Into

Crystal structures of human mitochondrial 3-ketoacyl-CoA thiolase (hT1) in the apo form and in complex with CoA have been determined at 2.0 Å resolution. The structures confirm the tetrameric quaternary structure of this degradative thiolase. The active site is surprisingly similar to the active site of theZoogloea ramigerabiosynthetic tetrameric thiolase (PDB entries 1dm3 and 1m1o) and different from the active site of the peroxisomal dimeric degradative thiolase (PDB entries 1afw and 2iik). A cavity analysis suggests a mode of binding for the fatty-acyl tail in a tunnel lined by the Nβ2–Nα2 loop of the adjacent subunit and the Lα1 helix of the loop domain. Soaking of the apo hT1 crystals with octanoyl-CoA resulted in a crystal structure in complex with CoA owing to the intrinsic acyl-CoA thioesterase activity of hT1. Solution studies confirm that hT1 has low acyl-CoA thioesterase activity for fatty acyl-CoA substrates. The fastest rate is observed for the hydrolysis of butyryl-CoA. It is also shown that T1 has significant biosynthetic thiolase activity, which is predicted to be of physiological importance.

scholarly journals Effects of microbial proteinase inhibitors on the degradation of endogenous and internalized proteins by rat yolk sacs

1981 ◽  
Vol 196 (1) ◽  
pp. 41-48 ◽  
Author(s):  
S E Knowles ◽  
F J Ballard ◽  
G Livesey ◽  
K E Williams
Keyword(s):  
Bovine Serum Albumin ◽  
Cathepsin B ◽  
Proteinase Inhibitors ◽  
Cathepsin L ◽  
Minor Role ◽  
Protein Breakdown ◽  
Inhibitory Effects ◽  
Endogenous Protein ◽  
A Minor

1. The effects of leupeptin and other microbial proteinase inhibitors were measured in rat yolk sacs on the uptake and degradation of formaldehyde-denatured 125I-labelled bovine serum albumin as well as on the degradation of 3H-labelled endogenous protein. 2. Leupeptin, at concentrations between 1 and 100 micrograms/ml, inhibits the degradation of added albumin without affecting pinocytic uptake. Accordingly large amounts of undegraded albumin accumulate within the tissue. 3. Removal of leupeptin produces a rapid recovery of the capacity to degrade albumin. 4. Endogenous protein degradation is rapidly inhibited by leupeptin, but to a far lesser extent than the breakdown of albumin. However, the inhibition is only slightly reversed on removal of leupeptin. 5. Degradation of both albumin and endogenous protein in intact yolk sacs is inhibited by the microbial proteinase inhibitors in the order: leupeptin greater than antipain greater than chymostatin; elastatinal, pepstatin and bestatin are ineffective. 6. Similar results are found when albumin is incubated in yolk-sac homogenates at pH 4 with the inhibitors. 7. The marked inhibitory effects of leupeptin, antipain and chymostatin suggest that cathepsin B and possibly cathepsin L participate in the degradation of 125I-labelled albumin in yolk sacs. By comparison, the smaller inhibitory effects of the proteinase inhibitors on endogenous protein breakdown imply a minor role of lysosomal cathepsins in this process.

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