Indirect evidence suggests that immunoglobulin A1 (IgA1) proteases may be factors in the pathogenesis of certain infectious diseases, including meningitis, gonorrhoea, and destructive periodontitis. Bacterial IgA1 proteases are ...
PubMed Central
Immunoglobulin A1 (IgA1) proteases from Haemophilus influenzae are extracellular proteases that specifically cleave the hinge region of human IgA1, the predominant class of immunoglobulin present on mucosal membranes. The IgA1 ...
Immunoglobulin A1 (IgA1) protease, an enzyme that selectively cleaves human IgA1, may be a virulence factor for pathogenic organisms such as Neisseria gonorrhoeae. Host protection from the effects of IgA1 protease includes ...
Bacteroides and Capnocytophaga species have been implicated as periodontal pathogens. Some of these species possess immunoglobulin A1 (IgA1) proteases that are capable of cleaving the human IgA1 molecule in the hinge region, leaving intact Fc alpha and ...
Attention has recently been focused on bacterial proteases with the capacity to cleave immunoglobulin A (IgA proteases) as possible pathogenic factors in bacterial meningitis, gonorrhoea, and destructive periodontal disease. Here, we describe a method for the rapid purification of a specific IgA1 ...
The purpose of this study was to determine the occurrence and nature of immunoglobulin A1 (IgA1) protease activity in members of the genus Gemella and related taxa. Among a total of 22 Gemella strains belonging to the four species Gemella haemolysans, Gemella morbillorum, ...
The pneumococcus expresses a protease that hydrolyzes human immunoglobulin A1 (IgA1). A gene for IgA1 protease was identified from a plasmid library of pneumococcal DNA because of the effect of its overexpression on the colony morphology of Streptococcus pneumoniae. The ...
Respiratory pathogens, such as Neisseria meningitidis, secrete site-specific proteases able to cleave human immunoglobulin A1 (IgA1), the first line of defense at mucosal membranes. Bacterial isolates show wide variability in IgA1 protease activity, and ...
The immunoglobulin A1 (IgA1) proteases of Neisseria gonorrhoeae have been defined as having human IgA1 as their single permissive substrate. However, in recent years there have been reports of other proteins which are susceptible to the proteolytic ...
Using a panel of 143 strains classified according to a novel taxonomic system for oral viridans-type streptococci, we reexamined the ability of oral streptococci to attack human immunoglobulin A1 (IgA1) molecules with IgA1 protease or glycosidases. IgA1 ...
PubMed
Recombinant proteins face major constraints along the plant cell secretory pathway, including proteolytic processing compromising their structural integrity. Here, we demonstrate the potential of protease inhibitors as in situ stabilizing agents for recombinant proteins migrating towards the leaf apoplast. Genomic data for Arabidopsis, rice and Nicotiana spp. were assessed to ...
All of 14 serotype standards and 34 of 35 wild-type strains of Ureaplasma urealyticum isolated from humans demonstrated an immunoglobulin A (IgA) protease activity. This activity degraded radiolabeled human IgA including IgA1 but not IgG or azocasein. The IgA fragments were detected by sodium ...
Immunoglobulin A (IgA) proteases are extracellular enzymes elaborated by Neisseria gonorrhoeae, N. meningitidis, and Streptococcus sanguis. These enzymes each cleave human IgA1 at a critically situated prolyl-threonly peptide bond to yield Factor B Alpha ...
National Technical Information Service (NTIS)
To understand more about the factors influencing the cleavage of immunoglobulin A1 (IgA1) by microbial IgA1 proteases, a recombinant human IgA2/IgA1 hybrid molecule was generated. In the hybrid, termed ...
The mechanisms by which immunoglobulin A1 (IgA1) protease activity may enable bacteria to evade the effect of specific secretory IgA (S-IgA) antibodies are not clear. A possibility which has received indirect experimental support is that bacteria, as a consequence of the ...
Many bacteria which establish infections after invasion at human mucosal surfaces produce enzymes which cleave immunoglobulin A (IgA), the primary immunoglobulin involved with protection at these sites. Bacterial species such as Haemophilus influenzae which produce IgA1 proteases secrete this enzyme into their environment. However, ...
The high-temperature requirement A (HtrA) family of serine proteases has been shown to play an important role in the environmental and cellular stress damage control system in Escherichia coli. Mycobacterium tuberculosis (Mtb) has three putative HtrA-like proteases, HtrA1, HtrA2, and HtrA3. The deletion of htrA2 ...
Energy Citations Database
Proteus mirabilis strains associated with human urinary tract infections have previously been shown to secrete an extracellular metalloproteinase which cleaves serum immunoglobulin A (IgA). The enzyme has now been purified to apparent homogeneity from culture supernatants of P. mirabilis 64676. The protease activity is associated with a 50-kilodalton (kDa) ...
Proteolytic degradation of extracellular matrix components has been suggested to play an essential role in the occurrence of ovulation. Recent studies in our laboratory have indicated that the plasminogen activator and matrix metalloproteinase systems, which were previously believed to be crucial for ovulation, are not required in this process. In this study we have used a ...
IgA, the major class of Ig in secretions, classically functions by interfering with microbial attachment to host tissues. Many mucosal pathogens, including Streptococcus pneumoniae, express an IgA1 protease that may circumvent the protective effects of this Ig subclass. Because these proteases are specific for human ...
The present invention discloses the use of bacterial IgA1 proteases to treat IgA1 deposition in tissue and organs. Bacterial IgA1 proteases specifically cleave IgA1 molecules and thus ...
Levels of HtrA1 protein in cartilage have been reported to elevate in joints of human osteoarthritis patients. To understand roles of HtrA1 in normal osteogenesis as well as in pathogenesis of arthritis, we examine HtrA1 expression pattern during bone and cartilage development and in articular cartilage affected by experimental arthritis. ...
Ureaplasma urealyticum strains of all serotypes express a specific human immunoglobulin A1 protease that cleaves immunoglobulin A1 to produce intact Fab and Fc fragments. The use of a variety of inhibitors suggests that the enzyme is a serine protease. N-terminal sequencing ...
Because immunoglobulin A (IgA) is the predominant immunoglobulin at mucosal surfaces, IgA proteases produced by pathogenic bacteria are considered potential virulence factors for organisms that cause disease or gain entry at mucous membranes. To determine the role of IgA protease in the pathogenicity of mycoplasmal disease, a variety of human and animal ...
The serine protease inhibitor a1-antitrypsin is the most potent inhibitor of human leukocyte elastase (HLE). The mechanism of inhibition of HLE by a 1-AT has not been clearly defined. We have synthesized linear and side-chain cyclized peptide analogs of t...
The serine protease, furin, is involved in the activation of a number of proteins most notably epithelial sodium channels (ENaC). The urea transporter UT-A1, located in the kidney inner medullary collecting duct (IMCD), is important for urine concentrating ability. UT-A1's ...
, in systems where caspases are not activated, other proteases, like serine proteases or cathepsins, serpins inhibit serine proteases by an irreversible suicide- substrate inhibitory mechanism. Protease mechanism involved in the change of the enzymatic activity of this ...
E-print Network
The effect of human secretory immunoglobulin A (S-IgA) and serum antibodies to surface protein antigen (Ag) I/II on the adherence of Ag I/II-bearing Streptococcus mutans and of free Ag I/II to saliva-coated hydroxyapatite (SHA) was investigated. The inhibition by S-IgA of binding of both S. mutans and free Ag I/II to SHA was dependent on antibody to Ag I/II. Essentially no difference was found ...
Human isolates of Streptococcus pneumoniae tested by traditional immunochemical methods produce a protease that cleaves human immunoglobulin A1 (IgA1) into Fab and Fc fragments. The protease may be an important virulence factor, but studies of its pathogenetic significance ...
This study is concerned with the co-production of alkaline proteases and thermostable alpha-amylase by some feather-degrading Bacillus strains: B. mojavensis A21, B. licheniformis NH1, B. subtilis A26, B. amyloliquefaciens An6 and B. pumilus A1. All strains produced both enzymes, except B. pumilus ...
Fusion proteins integrating dual pesticidal functions have been devised over the last 10 years to improve the effectiveness and potential durability of pest-resistant transgenic crops, but little attention has been paid to the impact of the fusion partners on the actual activity of the resulting hybrids. Here we assessed the ability of the rice cysteine ...
... Title : Fibroblast Activation Protein-Alpha, a Serine protease that Facilitates Metastasis by Modification of Diverse Microenvironments. ...
DTIC Science & Technology
... Title : Fibroblast Activation Protein-Alpha, a Serine Protease That Facilitates Metastasis by Modification of Diverse Microenvironments. ...
Haemophilus parasuis, the bacterium responsible for Gl�sser's disease, is a pathogen of significant concern in modern high-health swine production systems but there is little information regarding the identity or function of its virulence factors. Several important human mucosal pathogens, including the closely related bacterium Haemophilus influenzae, utilize IgA proteases ...
Human HtrA2 is part of the HtrA family of ATP-independent serine proteases that are conserved in both prokaryotes and eukaryotes and localizes to the intermembrane space of the mitochondria. Several recent reports have suggested that HtrA2 is important for maintaining proper mitochondrial homeostasis and may play a role in Alzheimer�s disease (AD), which is characterized by ...
In the bovine respiratory tract, IgG1 is a major secretory immunoglobulin (Ig), and both IgG1 and IgG2 are believed to be important in defense against pneumonic pasteurellosis (shipping fever) in calves. Here we provide evidence for hydrolysis of IgG1 in the presence of partially purified culture supernate (ppCS) from the respiratory pathogen Pasteurella haemolytica ...
... The determinations of protease activities in the sperm preparations (Table 1) suggest possible localization sites of these proteases ... ...
NBII National Biological Information Infrastructure
... The unknown protease: (a) is a non-caspase cytsteine protease; (b) cleaves p53, lamin Beta and PARP (atypically) in an NQO1-dependent manner ...