Partial immunological characterization of heat‐stable proteinases from <b><i>Pseudomonas</i></b> spp. of dairy origin

Azcona, Juan I.; Martı́n, Rosario; Hernández, Pablo E.; Sanz, B.

doi:10.1111/j.1365-2672.1989.tb02473.x

Cited by 8 publications

(5 citation statements)

References 30 publications

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“…Proteolytic supernatants from nonpseudomonads with related proteinase systems (31) did not react with the antibody, and lack of reactivity was also observed for proteolytic supernatants from P. aeruginosa DSM 50071. Hence, the antibody was specific for a subgroup of the alkaline proteinases in Pseudomonas, as shown for comparable proteinase antibodies (2,47). Nevertheless, the grouping by UP-PCR profiles and subsequent Western blot analysis of representative isolates strongly indicates that AprXlike proteinases were widespread among proteolytic pseudomonads in Lake Esrum, because the 10 most abundant UP-PCR groups accounted for 55% of the isolated strains.…”

Section: Microbial Dynamics In Microcosmsmentioning

confidence: 70%

“…Several proteolytic strains are well characterized due, e.g., to their deterioration of milk (8) and meat products (29). Several proteinase enzymes have been characterized (14), and antibodies have been raised to some of them (2,33,47). The above properties make Pseudomonas an attractive target group for studies that address how protein amendment can affect the expression of a proteolytic potential and influence the dynamics and composition of specific bacterial populations.…”

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confidence: 99%

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Input of Protein to Lake Water Microcosms Affects Expression of Proteolytic Enzymes and the Dynamics ofPseudomonasspp

Worm¹,

Nybroe²

2001

Appl Environ Microbiol

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The objective of this study was to determine how an input of protein to lake water affects expression of a proteolytic potential and influences the abundance and composition of a specific group of bacteria. Pseudomonas spp. were chosen as a target group that can be recovered on selective growth media and contain both proteolytic and nonproteolytic strains. Amendment with 2 mg of casein per liter increased total proteinase activity (hydrolysis of [ 3 H]casein) by 74%, leucine-aminopeptidase activity (hydrolysis of leucine-methylcoumarinylamide) by 133%, bacterial abundance by 44%, and phytoplankton biomass (chlorophyll a) by 39%. The casein amendment also increased the abundance of culturable Pseudomonas spp. by fivefold relative to control microcosms but did not select for proteolytic isolates. Soluble proteins immunochemically related to the Pseudomonas fluorescens alkaline proteinase, AprX, were detected in amended microcosms but not in the controls. The expression of this class of proteinase was confirmed exclusively for proteolytic Pseudomonas isolates from the microcosms. The population structure of Pseudomonas isolates was determined from genomic fingerprints generated by universally primed PCR, and the analysis indicated that casein amendment led to only minor shifts in population structure. The appearance of AprX-like proteinases in the lake water might thus reflect a general induction of enzyme expression rather than pronounced shifts in the Pseudomonas population structure. The limited effect of casein amendment on Pseudomonas population structure might be due to the availability of casein hydrolysates to bacteria independent of their proteinase expression. In the lake water, 44% of the total proteinase activity was recovered in 0.22-m-pore-size filtrates and thus without a direct association with the bacteria providing the extracellular enzyme activity. Since all Pseudomonas isolates expressed leucine-aminopeptidase in pure culture, proteolytic as well as nonproteolytic pseudomonads were likely members of the bacterial consortium that metabolized protein in the lake water.

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Section: Microbial Dynamics In Microcosmsmentioning

confidence: 70%

mentioning

confidence: 99%

Input of Protein to Lake Water Microcosms Affects Expression of Proteolytic Enzymes and the Dynamics ofPseudomonasspp

Worm¹,

Nybroe²

2001

Appl Environ Microbiol

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“…The misidentification within the P. fluorescens group and an overestimation of the relevance of P. fluorescens in milk and dairy products spoilage has led to a large number of works focused on purification and characterization of heat-resistant peptidase produced by the so-called species P. fluorescens ( Azcona et al, 1989 ; Kohlmann et al, 1991 ; Kim et al, 1997 ; Liao and McCallus, 1998 ; Matselis and Roussis, 1998 ; Costa et al, 2002 ; McCarthy et al, 2004 ; Maunsell et al, 2006 ; Dufour et al, 2008 ; Mu et al, 2009 ; Martins et al, 2015 ; Zhang et al, 2015 ). Although acknowledging this problem, the species name as described in the, respectively, cited literature will be retained in this review.…”

Section: Heat-stable Spoilage Enzymes Produced By Psychrotrophic Micrmentioning

confidence: 99%

The Biodiversity of the Microbiota Producing Heat-Resistant Enzymes Responsible for Spoilage in Processed Bovine Milk and Dairy Products

et al. 2017

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Raw bovine milk is highly nutritious as well as pH-neutral, providing the ideal conditions for microbial growth. The microbiota of raw milk is diverse and originates from several sources of contamination including the external udder surface, milking equipment, air, water, feed, grass, feces, and soil. Many bacterial and fungal species can be found in raw milk. The autochthonous microbiota of raw milk immediately after milking generally comprises lactic acid bacteria such as Lactococcus, Lactobacillus, Streptococcus, and Leuconostoc species, which are technologically important for the dairy industry, although they do occasionally cause spoilage of dairy products. Differences in milking practices and storage conditions on each continent, country and region result in variable microbial population structures in raw milk. Raw milk is usually stored at cold temperatures, e.g., about 4°C before processing to reduce the growth of most bacteria. However, psychrotrophic bacteria can proliferate and contribute to spoilage of ultra-high temperature (UHT) treated and sterilized milk and other dairy products with a long shelf life due to their ability to produce extracellular heat resistant enzymes such as peptidases and lipases. Worldwide, species of Pseudomonas, with the ability to produce these spoilage enzymes, are the most common contaminants isolated from cold raw milk although other genera such as Serratia are also reported as important milk spoilers, while for others more research is needed on the heat resistance of the spoilage enzymes produced. The residual activity of extracellular enzymes after high heat treatment may lead to technological problems (off flavors, physico-chemical instability) during the shelf life of milk and dairy products. This review covers the contamination patterns of cold raw milk in several parts of the world, the growth potential of psychrotrophic bacteria, their ability to produce extracellular heat-resistant enzymes and the consequences for dairy products with a long shelf life. This problem is of increasing importance because of the large worldwide trade in fluid milk and milk powder.

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“…The activity and stability of protease at various temperatures needs further study. ELISA using protein-F, toxins, or whole cells as antigens are used for detection of Pseudomonas species in milk, dairy products and meat (Azcona et al, 1989;Gonzalez et al, 1994;Eriksson et al, 1995). In our work, protease enzyme produced by Pseudomonas species was used as an antigen for the development of a wholly indige-nous ELISA system and applied to seafoods for the first time.…”

Section: Resultsmentioning

confidence: 99%

Rapid Detection of Pseudomonas in Seafoods Using Protease Indicator

Jabbar

Joishy

1999

Journal of Food Science

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The effects of Pseudomonas and the proteases it synthesizes in seafoods rendering them unfit for consumption are not fully recognized. A sandwich enzymelinked immunosorbent assay (ELISA) was developed wherein protease produced by Pseudomonas isolated from shrimp was used as antigen, and anti-protease IgG conjugated with alkaline phosphatase was the second antibody. Purified protease and seafood samples, naturally contaminated or artificially inoculated with Pseudomonas, were positive by ELISA. The conventional culture method took 3 days to complete, but ELISA detected Pseudomonas within 24h. The rapidity, simplicity and efficacy of this test make it useful for implementation of HACCP systems.

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Partial immunological characterization of heat‐stable proteinases from Pseudomonas spp. of dairy origin

Cited by 8 publications

References 30 publications

Input of Protein to Lake Water Microcosms Affects Expression of Proteolytic Enzymes and the Dynamics ofPseudomonasspp

Input of Protein to Lake Water Microcosms Affects Expression of Proteolytic Enzymes and the Dynamics ofPseudomonasspp

The Biodiversity of the Microbiota Producing Heat-Resistant Enzymes Responsible for Spoilage in Processed Bovine Milk and Dairy Products

Rapid Detection of Pseudomonas in Seafoods Using Protease Indicator

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