Purification and Properties of Bacterial Urease

Abstract

Various groups of ureolytic organisms have been investigated from the point of view of taxonomic considerations (Viehover, 1913) or with special emphasis on nutritional requirements (Gibson, 1934; Knight and Proom, 1950). However, less attention has been paid to the charactexization of bacterial urease despite the fact that the enzyme has been reported to occur in 200 species of bacteria (Sumner and Somers, 1947). Sizer (1941) determined the kinetics of bacterial urease, and in an earlier study Pasmore and Yudkin (1937) investigated the relationship of growth on diverse substrates to the final level of urease in the harvested organisms. In both of these studies, intact cells of Proteus vulgaris were used as a source of enzyme. So far as we are aware, no report has ever appeared on the purification and properties of urease of bacteria. The present work is a report on such a purification and a comparison of the properties of highly active bacterial urease with urease from other sources. MATERIALS AD METODS Numerous strains of ureolytic bacilli were examined, and since BaciUlu pasteurii (U.S.D.A. 673, Gibson no. 22) possessed relatively high enzymatic activity, it was employed throughout this study. The urea incorporated into all media was sterilized by filtration or intermittent steaming and added to the autoclaved media. Organisms were subcultured on two per cent urea meat infusion slants at room temperature. For growing cells in quantity 40 liters of medium (yeast extract, 0.7 per cent; polypeptone, 1.0 per cent; urea, 2 per cent) were distributed in 12 liter carboys and inoculated with the 24 hour growth

Purification and subunit determination of the nickel-dependent Staphylococcus xylosus urease

“…The purified S. xylosus C2a urease had a maximum specific activity of 1573 U/mg. Similar values have been described for the Bacillus pasteurii urease [2,13] and a maximum specific activity as high as 3 750 U/mg was obtained with the enzyme of B. ammoniagenes [3]. Purification of ureases from most other Gram-positive organisms, however, only resulted in significantly lower specific activities [1].…”

Effects of salt and nickel ion on the conformational stability ofBacillus pasteuriiUreE

“…Since alkalophilic B. pasteurii has been known for its remarkable urease production [17], its ure gene cluster was previously cloned, and subsequently the composition of the accessory genes as well as the precise genetic organization were reported by You et al [10,18]. Very recently, another independent work on the cloning, sequencing, and analyzing of the B. pasteurii urease operon containing all four accessory genes was reported by Ciurli et al [11].…”

Microbial ureases: significance, regulation, and molecular characterization.

“…The high cellular content of urease in some microbes suggests that this protein may have functions in addition to catalytic activity. For example, urease makes up 1% of the cell dry weight of Bacillus paistelurii, a common soil bacterium (123), and 8.5% of the total soluble protein of the fungus Asper-gillu(s tailfl(iii (248). In Aspergilluts tafiarii.…”