Pseudomonas Keratitis: Protease IV Gene Conservation, Distribution, and Production Relative to Virulence and OtherPseudomonasProteases

Caballero, Armando R.; Thibodeaux, Brett A.; Marquart, Mary E.; Traidej, Mullika; O’Callaghan, Richard J.

doi:10.1167/iovs.03-1050

Cited by 40 publications

(51 citation statements)

References 46 publications

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“…However, the ability to withstand surfactant and stability in solvent medium is a lesser-known quality of these enzymes. P. aeruginosa has been reported to produce at least four different types of endopeptidases [Kessler et al 1998;Traidej et al, 2003]: (i) elastase or pseudolysin (LasB) -a 33-kDa zinc metallopeptidase [Kessler and Ohman, 2004a;Ogino et al, 2000], (ii) staphylolysin or LasA endopeptidase -a 20-kDa zinc metalloendopeptidase [Kessler et al, 1998;Kessler and Ohman, 2004b], (iii) alkaline protease or aeruginolysin -a 50-kDa zinc metalloendopeptidase [Morihara and Homma, 1985;Okuda et al, 1990;Wallach, 2004] and (iv) protease IV or lysyl endopeptidase -a 26-kDa serine protease encoded by protease IV gene [Caballero et al, 2004;Engel et al, 1998]. Of these, the alkaline protease and elastase (both metalloproteases) have been reported to be the most abundant ones [Parmely, 1993].…”

Section: Introductionmentioning

confidence: 99%

Solvent-Stable Pseudomonas aeruginosa PseA Protease Gene: Identification, Molecular Characterization, Phylogenetic and Bioinformatic Analysis to Study Reasons for Solvent Stability

et al. 2007

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We have previously isolated a solvent-stable protease from a novel solvent-tolerant strain of Pseudomonasaeruginosa (PseA). Here we report cloning and characterization of the gene coding for this solvent-tolerant protease. A homology search of the N-terminal amino acid sequence of the purified PseA protease revealed an exact match to a P. aeruginosa PST-01 protease gene, lasB. The c-DNA sequence of the PST-01 protease was used to design primers for the amplification of a 1,494-bp open reading frame encoding a 53.6-kDa, 498-amino-acid PseA LasB polypeptide.The deduced PseA LasB protein contained a 23-residue signal peptide (2.6 kDa) followed by a propeptide of 174 residues and a 33-kDa mature product of 301 residues. A phylogenetic analysis placed PseA lasB closest to the known zinc metalloproteases from P. aeruginosa. This gene was also found to contain a conserved HEXXH zinc-binding motif, characteristic of all zinc metallopeptidases. The 3D structure analysis of PseA protease revealed the presence of 7 α-helices (36% of the sequence). The molecule was found to have two disulfide bonds (between Cys-227 and Cys-255 and between Cys-467 and Cys-494) and had a number of hydrophobic clusters at the protein surface. These hydrophobic patches (21% of the sequence) and disulfide bonds may possibly be responsible for the solvent-stable nature of the enzyme.

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Section: Introductionmentioning

confidence: 99%

Solvent-Stable Pseudomonas aeruginosa PseA Protease Gene: Identification, Molecular Characterization, Phylogenetic and Bioinformatic Analysis to Study Reasons for Solvent Stability

et al. 2007

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“…13 However, Caballero et al have demonstrated that significant alkaline protease activity can be produced by this strain. 12 Similarly, Marquart et al have shown that P. aeruginosa can modulate the expression of protease in response to environmental levels of magnesium and/or calcium. 56 Additionally, Marquart et al have recently discovered an additional protease that was not formerly recognized as a product of P. aeruginosa.…”

Section: Discussionmentioning

confidence: 97%

“…29,31,35 Unfortunately, these protease-deficient mutants retained their ability to produce protease IV, a known corneal virulence factor. 12,13 Thus, the loss of elastase B or alkaline protease could have been compensated for, in terms of ocular virulence, by the continued production of other proteases (e.g., protease IV).…”

Section: Discussionmentioning

confidence: 99%

Corneal Virulence ofPseudomonas aeruginosaElastase B and Alkaline Protease Produced byPseudomonas putida

Thibodeaux

Caballero

Marquart

et al. 2007

Current Eye Research

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“…To understand the mechanism of pathogenesis in keratitis caused by P. aeruginosa, the virulence factors as well as extracellular products, including proteases, [6][7][8] exotoxin A, 9 and biofilms, 10 have been investigated. Of these factors, proteases, including metalloproteases such as alkaline protease, elastase A, and elastase B, 11 are important in virulence.…”

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confidence: 99%

Relationship of Virulence Factors and Clinical Features in Keratitis Caused byPseudomonas aeruginosa

Oka

Suzuki

Ishikawa

et al. 2015

Invest. Ophthalmol. Vis. Sci.

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PURPOSE. To examine bacterial virulence factors in Pseudomonas aeruginosa isolates from contact lens (CL) wearers and non-CL wearers with P. aeruginosa keratitis, and to investigate relationships between virulence factors and clinical features of keratitis.METHODS. The study involved 25 subjects including 18 CL and 7 non-CL-related P. aeruginosa keratitis patients. Slit-lamp photographs of all subjects were captured, and the focus occupancy ratio (FOR) was defined as the total focus area/entire cornea area, using image processing software. Twenty-five clinical P. aeruginosa isolates from keratitis were assessed for protease production, elastase production, biofilm formation, bacterial swimming and swarming motility, cell surface hydrophobicity, and genes encoding the type III secretion system (TTSS) effectors (ExoU and ExoS). RESULTS.Ring abscess was found in 9 of 18 CL-related P. aeruginosa keratitis cases (CL[þ] ring[þ] group) but not in another 9 cases (CL[þ] ring[À] group). Expression or prevalence of virulence factors in P. aeruginosa isolates from the CL(þ) ring(þ) group, CL(þ) ring(À) group, and CL(À) group were compared. The FOR for CL(þ) ring(þ) or CL(À) was higher than for CL(þ) ring(À) (P < 0.05 and P < 0.01, respectively). The rate of positive swimming motility for CL(þ) ring(þ) or CL(À) was higher than for CL(þ) ring(À) (P < 0.05), whereas the rate of positive swarming motility for CL(þ) ring(þ) was higher than for CL(þ) ring(À) or CL(À) (P < 0.05). Prevalence of an exoSþ/exoU-genotype for CL(þ) ring(þ) or CL(À) was higher than for CL(þ) ring(À) (P < 0.05). In the CL-related group, expression of elastase and swarming motility significantly correlated with FOR.CONCLUSIONS. Swimming motility, swarming motility, and TTSS ExoS could play a major role in the determination of clinical features of P. aeruginosa keratitis.Keywords: Pseudomonas aeruginosa, keratitis, virulence factors, protease, swarming motility K eratitis caused by Pseudomonas aeruginosa can progress rapidly with suppurative infiltration, and can lead to corneal perforation and melt, resulting in the loss of vision. 1Contact lens (CL) wearers are especially susceptible to development of P. aeruginosa keratitis. Ring abscess, which is a ring-shaped accumulation of polymorphonuclear leukocytes surrounding a central corneal lesion, is a well-known hallmark of P. aeruginosa keratitis.2,3 Along with ring abscess, serrated or satellite lesions with keratitis are sometimes found in P. aeruginosa keratitis.4,5 Pseudomonas aeruginosa can show various clinical features, but little is known about factors that determine these clinical features.To understand the mechanism of pathogenesis in keratitis caused by P. aeruginosa, the virulence factors as well as extracellular products, including proteases, 6-8 exotoxin A, 9 and biofilms, 10 have been investigated. Of these factors, proteases, including metalloproteases such as alkaline protease, elastase A, and elastase B, 11 are important in virulence. We recently reported that MucD protease inhibits neu...

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Pseudomonas Keratitis: Protease IV Gene Conservation, Distribution, and Production Relative to Virulence and OtherPseudomonasProteases

Abstract: The protease IV gene and its product are common to P. aeruginosa, but not to other Pseudomonas species. Protease IV activity varies among P. aeruginosa strains, and a mutant specifically deficient in this activity produced alkaline protease and had reduced corneal virulence.

Cited by 40 publications

References 46 publications

Solvent-Stable <i>Pseudomonas aeruginosa</i> PseA Protease Gene: Identification, Molecular Characterization, Phylogenetic and Bioinformatic Analysis to Study Reasons for Solvent Stability

Solvent-Stable <i>Pseudomonas aeruginosa</i> PseA Protease Gene: Identification, Molecular Characterization, Phylogenetic and Bioinformatic Analysis to Study Reasons for Solvent Stability

Corneal Virulence ofPseudomonas aeruginosaElastase B and Alkaline Protease Produced byPseudomonas putida

Relationship of Virulence Factors and Clinical Features in Keratitis Caused byPseudomonas aeruginosa

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