Gene Ontology annotation through association of InterPro records with GO terms
Annotation inferences using phylogenetic trees
Combined Automated Annotation using Multiple IEA Methods
Efficient production and processing of elastase and LasA by Pseudomonas aeruginosa require zinc and calcium ions.
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Proteolytic and elastolytic activity of P. aeruginosa supernatants requires both zinc and calcium in the medium and tracks with the appearance of the mature 33 kDa elastase; activity of the calcium-starved 33 kDa enzyme is recovered by adding zinc to the assay.
"High levels of proteolytic and elastolytic activity were exhibited by all strains when cultured in the presence of both zinc and calcium, and this was associated with the production of mature 33-kDa elastase and 21-kDa LasA."
Synthesis, processing, and transport of Pseudomonas aeruginosa elastase.
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Elastase is synthesised as a precursor, processed in the periplasm, and transported to the extracellular medium; expression responds to the metal content of the medium.
"Synthesis, processing, and transport of Pseudomonas aeruginosa elastase."
Secretion of elastinolytic enzymes and their propeptides by Pseudomonas aeruginosa.
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Both the mature elastase and its propeptide are secreted, the propeptide being degraded extracellularly; loss of extracellular proteolytic activity leaves LasA, LasD and a Streptomyces-aminopeptidase homologue unprocessed in the medium.
"We demonstrate that the propeptide and the mature elastase are both secreted but that the propeptide is degraded extracellularly."
Substitution of active-site His-223 in Pseudomonas aeruginosa elastase and expression of the mutated lasB alleles in Escherichia coli show evidence for autoproteolytic processing of proelastase.
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His-223 of the mature chain (His420 of the precursor) is essential for proteolytic and elastolytic activity, and pro-elastase maturation is autocatalytic: the mutants accumulate the 51 kDa pro-enzyme, which exogenous purified elastase processes in trans.
"The present results confirm that His-223 is essential for elastase activity and provide evidence for autoproteolytic processing of proelastase."
Three-dimensional structure of the elastase of Pseudomonas aeruginosa at 1.5-A resolution.
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The 1.5 A structure shows a thermolysin-like fold with one catalytic Zn(2+) and one Ca(2+); the active-site residues are nearly identical to thermolysin but the cleft is more open.
"The overall tertiary structure of the PAE molecule is similar to that of thermolysin, with which it shares 28% amino acid sequence identity."
A secreted aminopeptidase of Pseudomonas aeruginosa. Identification, primary structure, and relationship to other aminopeptidases.
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Conversion of the secreted aminopeptidase AP56 to the active 28 kDa form depends on elastase, so LasB matures another secreted P. aeruginosa enzyme.
"Heating (70 degrees C) of the partially purified aminopeptidase preparations led to the conversion of AP(56) to a approximately 28-kDa protein (AP(28)) that retained enzyme activity, a reaction that depended on elastase (LasB)."
Swarming of Pseudomonas aeruginosa is a complex adaptation leading to increased production of virulence factors and antibiotic resistance.
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lasB is induced under swarming conditions and lasB mutants are impaired in swarming and form about half as much biofilm; both phenotypes are complemented by a chromosomal lasB copy.
"Elastase LasB and PvdQ are essential for normal swarming behavior."
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The authors attribute the phenotypes to LasB secretion, noting that T2SS mutants behave similarly.
"Our results are consistent with the secretion of LasB by the type II secretion system, since mutants with defects in this secretion apparatus also exhibit strong swarming and biofilm defects ( 41 )."
Pseudomonas aeruginosa Elastase Contributes to the Establishment of Chronic Lung Colonization and Modulates the Immune Response in a Murine Model.
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LasB is the most abundant P. aeruginosa protease, degrades extracellular matrix and complement components, and its deletion in an early-persistence clinical isolate reduces bacterial burden in a murine persistent-pneumonia model.
"The zinc metalloprotease elastase B (also called LasB or pseudolysin) is the most abundant protease in the P."
Anti-quorum sensing and antibiofilm potential of Alternaria alternata, a foliar endophyte of Carica papaya, evidenced by QS assays and in-silico analysis.
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A fungal extract reduced quorum-sensing-dependent phenotypes of P. aeruginosa, including LasB elastase activity in culture supernatants.
"significant decrease in proteases activity such as LasA protease activity, staphylolytic activity, Las B elastase"