THE IgA1 PROTEASES OF PATHOGENIC BACTERIA

Plaut, Andrew G.

doi:10.1146/annurev.mi.37.100183.003131

Cited by 285 publications

(182 citation statements)

References 0 publications

Supporting

Mentioning

174

Contrasting

Unclassified

Order By: Relevance

“…Thus far, an IgA-degrading protease (ZapA) is the only protease that has been identified in P. mirabilis (Wassif et al, 1995) and no virulence studies have yet been conducted using isogenic mutants. However, alignment of the respective predicted amino acid sequences demonstrates that there is no similarity between the B2 gene product and this IgA-degrading protease or to those of other mucosal pathogens including Neisseria gonorrhoeae (Plaut et al, 1975) and Haemophilus influensae (Plaut, 1983). Instead, the B2 gene encodes a protein that is related to the U32 peptidase family.…”

Section: Discussionmentioning

confidence: 98%

Identification of protease and rpoN-associated genes of uropathogenic Proteus mirabilis by negative selection in a mouse model of ascending urinary tract infection

Zhao

Johnson

et al. 1999

Microbiology

View full text Add to dashboard Cite

Proteus rnirabilis, a motile Gram-negative bacterium, is a principal cause of urinary tract infections in patients with functional or anatomical abnormalities of the urinary tract or those with urinary catheters in place. Thus far, virulence factors including urease, flagella, haemolysin, various fimbriae, IgA protease and a deaminase have been characterized based on the phenotypic traits conferred by these proteins. In this study, an attempt was made to identify new virulence genes of P. rnirabilis that may not have identifiable phenotypes using the recently described technique of signature-tagged mutagenesis. A pool of chromosomal transposon mutants was made through conjugation and kanamycin/tetracycl ine selection; random insertion was confirmed by Southern blotting of chromosomal DNA isolated from 16 mutants using the aphA gene as a probe. From the total pool, 2.3% (9/397) auxotrophic mutants and 3.5% (14/397) swarming mutants were identified by screening on minimal salts agar and Luria agar plates, respectively. T h i r t y per cent of the mutants, found to have either no tag or an unamplifiable tag, were removed from the input pool. Then lo7 c.f.u. from a 96-mutant pool (-lo5 c.f.u. of each mutant) were used as an input pool to transurethrally inoculate seven CBA mice. After 2 d infection, bacteria were recovered from the bladders and kidneys and yielded about l o 5 c.f.u. as an output pool. Dot blot analysis showed that two of the 96 mutants, designated B2 and B5, could not be hybridized by signature tags amplified from the bladder output pool. Interrupted genes from these two mutants were cloned and sequenced. The interrupted gene in B2 predicts a polypeptide of 37-3 kDa that shares amino acid similarity with a putative protease or collagenase precursor. The gene in B5 predicts a polypeptide of 32-6 kDa that is very similar to that encoded by ORF284 of the rpoN operon controlling expression of nitrogen-regulated genes from several bacterial species. The virulence of the two mutants was tested further by co-challenging CBA mice with each mutant and the parental strain. After 1 week of infection, the B2 and B5 mutants were recovered in numbers 100-fold and 1000-fold less than the parental strain, respectively. Using an in vitro assay, it was shown that the B2 mutant had significantly less (P = O*OOOl) extracellular protease activity than the wild-type strain. These findings demonstrate that signaturetagged mutagenesis is a viable approach to identify bacterial genes associated with the ability to infect the urinary tract.

show abstract

Section: Discussionmentioning

confidence: 98%

Identification of protease and rpoN-associated genes of uropathogenic Proteus mirabilis by negative selection in a mouse model of ascending urinary tract infection

Zhao

Johnson

et al. 1999

Microbiology

View full text Add to dashboard Cite

show abstract

“…Because IgA is a predominant immunoglobulin in the secretions of mammalians, and plays a role in the first line of defense against exogenous pathogens and antigenic macromolecules (3,12,18,19,23), the IgA proteases have been regarded as virulence factors allowing these organisms to escape this mucosal defense (14). However, all of these IgA proteases have been shown to have substrate specificity only for human IgA of IgAl subclass, and are called IgAl proteases.…”

mentioning

confidence: 99%

Clostridium ramosum, an IgA Protease‐Producing Species and Its Ecology in the Human Intestinal Tract

Senda¹,

Fujiyama²,

Ushijima³

et al. 1985

Microbiology and Immunology

View full text Add to dashboard Cite

A bacterial strain isolated from feces of a patient with ulcerative colitis, which had been shown to produce a novel immunoglobulin A (IgA) protease (cleaving both the human IgAl subclass and IgA2 subclass of A2m(1) allotype) extracell ularly, was identified as Clostridium ramosum. By using a selective medium (proprionate-rifampicin-gentamicin-colimycin-polymyxin medium) devised for C. ramosu m, analysis of the population level of this organism was performed to determine its ecology in the human intestinal tract. C. ramosum was isolated in 20 of 25 fecal samples (80%) from patients with inflammatory bowel disease (I.B.D.) and in 112 of 135 samples (83%) from patients without I.B.D. (control group). C. ramosum was also isolated from 6 of 11 biopsy samples (55%) of the inflamed rectal mucosa from patients with ulcerative colitis and from five of 15 samples (33%) from the intact mucosa of the control group. The population levels of C. ramosum in most of the biopsy samples ranged from 2.3 to 5.0 logic, per gram. The IgA protease-positive C. ramosum was found in only four of 135 fecal samples (3%) and one of 15 biopsy samples (6.7% ) from the control group. These results indicate that IgA protease-positive C. ramosu m is not likely to play a role in the induction of I.B.D., unless the organism is first isolated from the patient with I.B.D.

show abstract

“…To escape from host immune responses, some bacteria secrete proteinases to degrade host immunoglobulins. Protozoa such as G. lamblia, E. histolytica and T. vaginalis also secrete cysteine proteinases which degrade the host immunoglobulins (Plaut, 1983;Parenti, 1989;Kelsall and Ravdin, 1993;Provenzano and Alderete, 1995;Min et al, 1997). In this study, the purified cysteine proteinase degraded immunoglobulins, suggesting that T. vaginalis can escape from host immune surveillance by degrading IgA and secretory IgA.…”

Section: Effect Of Proteinase Inhibitorsmentioning

confidence: 66%

Degradations of human immunoglobulins and hemoglobin by a 60 kDa cysteine proteinase of Trichomonas vaginalis

et al. 1998

View full text Add to dashboard Cite

THE IgA1 PROTEASES OF PATHOGENIC BACTERIA

Cited by 285 publications

References 0 publications

Identification of protease and rpoN-associated genes of uropathogenic Proteus mirabilis by negative selection in a mouse model of ascending urinary tract infection

Identification of protease and rpoN-associated genes of uropathogenic Proteus mirabilis by negative selection in a mouse model of ascending urinary tract infection

Clostridium ramosum, an IgA Protease‐Producing Species and Its Ecology in the Human Intestinal Tract

Degradations of human immunoglobulins and hemoglobin by a 60 kDa cysteine proteinase of Trichomonas vaginalis

Contact Info

Product

Resources

About