Haemophilus paragallinarumsecretes metalloproteases

2005 ◽  
Vol 51 (10) ◽  
pp. 893-896 ◽  
Author(s):  
P C Rivero-García ◽  
C Vázquez Cruz ◽  
P Sánchez Alonso ◽  
S Vaca ◽  
E Negrete-Abascal
Keyword(s):  
Molecular Mass ◽  
Proteolytic Activity ◽  
Culture Media ◽  
High Molecular Mass ◽  
Secreted Proteins ◽  
Extracellular Proteases ◽  
Heat Stable ◽  
Infectious Coryza ◽  
Ph Range ◽  
Polyclonal Serum

Haemophilus paragallinarum secretes metalloproteases into different culture media lacking serum. Secreted proteins, concentrated by precipitation with 70% ammonium sulphate ((NH4)2SO4) or methanol, displayed proteolytic activity at >100 kDa molecular mass in 10% polyacrylamide gels co-polymerized with porcine gelatin (0.1%). They were active in a broad pH range (4–9); pH 7.5 being the optimum. Protease activity was inhibited by 20 mmol EDTA/L and reactivated by calcium. The proteolytic activity was heat-stable at 40, 50, and 60 °C, but its activity diminished at 70 °C or higher. Secreted proteins partially degraded chicken immunoglobulin G (IgG) and cross-reacted with a polyclonal serum against a high molecular mass protease secreted by Actinobacillus pleuropneumoniae. Extracellular proteases could play a role in infectious coryza caused by H. paragallinarum.Key words: pathogenicity, secreted protein, infectious coryza.

Enzymic Proteolysis byEntamoeba histolytica; biochemical characteristics and relationship with invasiveness

Parasitology ◽  
1960 ◽  
Vol 50 (3-4) ◽  
pp. 531-550 ◽  
Author(s):  
R. A. Neal
Keyword(s):  
Proteolytic Activity ◽  
Culture Media ◽  
Proteolytic Enzymes ◽  
Egg Yolk ◽  
Single Strain ◽  
High Proteolytic Activity ◽  
Serum Inhibitor ◽  
Sulphydryl Groups ◽  
Ph Range

The proteolytic activity of extracts ofEntamoeba histolyticahas been further investigated. Casein and gelatin, but not haemaglobin, were hydrolysed. Activity was observed in the pH range 5·8 to 8·5 with optimal activity at pH 7·5 to 7·9. Activity was optimal at 37° C. and sulphydryl groups were not required. Concomitant bacteria showed no proteolytic activity. Hyaluronidase, collagenase and lecithinase could not be detected.An inhibitor of proteolytic enzyme was present in sera of all animals tested and in egg yolk. All culture media prepared from eggs were inhibitory, but inspissation or dilution of serum inactivated the serum inhibitor. Purified trypsin inhibitors from lima and soy bean were not active against the amoebic enzyme. Proteolytic enzymes were not secreted extracellularlyin vitro.High proteolytic activity was found in two out of five invasive, freshly isolated, strains ofE. histolyticaand after two series of liver passages of a single strain. The significance of these observations is discussed. It is concluded that the present evidence does not convincingly demonstrate that high proteolytic activity is required for tissue invasion by amoebae, but may accompany another factor.

High molecular mass kininogen inhibits cathepsin G-induced platelet activation by forming a complex with cathepsin G

2001 ◽  
Vol 2 (6) ◽  
pp. 371-377 ◽  
Author(s):  
Tarek E Selim ◽  
Hayam R Ghoneim ◽  
Hassan A Abdel Ghaffar ◽  
Robert W Colman ◽  
Raul A Dela Cadena
Keyword(s):  
Molecular Mass ◽  
Platelet Activation ◽  
High Molecular Mass ◽  
Cathepsin G

scholarly journals Analysis of High Molecular Mass Compounds from the Spider Pamphobeteus verdolaga Venom Gland. A Transcriptomic and MS ID Approach

Toxins ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 453
Author(s):  
Sebastian Estrada-Gómez ◽  
Leidy Johana Vargas-Muñoz ◽  
Cesar Segura Latorre ◽  
Monica Maria Saldarriaga-Cordoba ◽  
Claudia Marcela Arenas-Gómez
Keyword(s):  
Enzymatic Activity ◽  
Molecular Mass ◽  
Evolutionary Relationship ◽  
Venom Gland ◽  
Duplication Event ◽  
High Molecular Mass ◽  
Amino Acid Sequences ◽  
Secretory Proteins ◽  
Phospholipases A2 ◽  
Kunitz Type

Nowadays, spider venom research focuses on the neurotoxic activity of small peptides. In this study, we investigated high-molecular-mass compounds that have either enzymatic activity or housekeeping functions present in either the venom gland or venom of Pamphobeteus verdolaga. We used proteomic and transcriptomic-assisted approaches to recognize the proteins sequences related to high-molecular-mass compounds present in either venom gland or venom. We report the amino acid sequences (partial or complete) of 45 high-molecular-mass compounds detected by transcriptomics showing similarity to other proteins with either enzymatic activity (i.e., phospholipases A2, kunitz-type, hyaluronidases, and sphingomyelinase D) or housekeeping functions involved in the signaling process, glucanotransferase function, and beta-N-acetylglucosaminidase activity. MS/MS analysis showed fragments exhibiting a resemblance similarity with different sequences detected by transcriptomics corresponding to sphingomyelinase D, hyaluronidase, lycotoxins, cysteine-rich secretory proteins, and kunitz-type serine protease inhibitors, among others. Additionally, we report a probably new protein sequence corresponding to the lycotoxin family detected by transcriptomics. The phylogeny analysis suggested that P. verdolaga includes a basal protein that underwent a duplication event that gave origin to the lycotoxin proteins reported for Lycosa sp. This approach allows proposing an evolutionary relationship of high-molecular-mass proteins among P. verdolaga and other spider species.

scholarly journals Identification of two highly sialylated human tear-fluid DMBT1 isoforms: the major high-molecular-mass glycoproteins in human tears

2002 ◽  
Vol 366 (2) ◽  
pp. 511-520 ◽  
Author(s):  
Benjamin L. SCHULZ ◽  
David OXLEY ◽  
Nicolle H. PACKER ◽  
Niclas G. KARLSSON
Keyword(s):  
Molecular Mass ◽  
Peptide Mass Fingerprinting ◽  
High Molecular Mass ◽  
Tear Fluid ◽  
Protein Variant ◽  
Peptide Mass ◽  
Composite Gel ◽  
Molecular Masses ◽  
Protein Components ◽  
Sialyl Lea

Human open eye tear fluid was separated by low-percentage SDS/PAGE to detect high-molecular-mass protein components. Two bands were found with apparent molecular masses of 330 and 270kDa respectively. By peptide-mass fingerprinting after tryptic digestion, the proteins were found to be isoforms of the DMBT1 gene product, with over 30% of the predicted protein covered by the tryptic peptides. By using gradient SDS/agarose/polyacrylamide composite gel electrophoresis and staining for glycosylation, it was shown that the two isoforms were the major high-molecular-mass glycoproteins of >200kDa in human tear fluid. Western blotting showed that the proteins expressed sialyl-Lea. After the release of oligosaccharides by reductive β-elimination from protein blotted on to PVDF membrane, it was revealed by liquid chromatography-MS that the O-linked oligosaccharides were comprised mainly of highly sialylated oligosaccharides with up to 16 monosaccharide units. A majority of the oligosaccharides could be described by the formula dHex0→2NeuAc1→xHexxHexNAcx(-ol), x = 1–6, where Hex stands for hexose, dHex for deoxyhexose, HexNAc for N-acetylhexosamine and NeuAc for N-acetylneuraminate. The number of sialic acids in the formula is less than 5. Interpretation of collision-induced fragmentation tandem MS confirmed the presence of sialic acid and suggested the presence of previously undescribed structures carrying the sialyl-Lea epitopes. Small amounts of neutral and sulphated species were also present. This is the first time that O-linked oligosaccharides have been detected and described from protein variant of the DMBT1 gene.

High-Molecular-Mass Receptors for Ammodytoxin in Pig Are Tissue-Specific Isoforms of M-Type Phospholipase A2 Receptor

2001 ◽  
Vol 289 (1) ◽  
pp. 143-149 ◽  
Author(s):  
Nina Vardjan ◽  
Nicholas E Sherman ◽  
Jože Pungerčar ◽  
Jay W Fox ◽  
Franc Gubenšek ◽  
...  
Keyword(s):  
Phospholipase A2 ◽  
Molecular Mass ◽  
High Molecular Mass ◽  
Tissue Specific ◽  
Phospholipase A2 Receptor
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