Bacterial α-Amylases

Ingle, M. B.; Erickson, Robert J.

doi:10.1016/s0065-2164(08)70643-9

Cited by 52 publications

(19 citation statements)

References 105 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Second, for the enzyme to be secreted at appropriate rates into environments that may vary widely in their effects on the activity and longevity ofthe enzyme, the rate of synthesis must be sensitive to the specific activity of the enzyme. Accordingly, it is generally assumed that extracellular depolymerases are "product induced" by the action ofthe same enzyme synthesized and secreted at basal levels (22)(23)(24)(25), and that, after induction, the accumulation of high concentrations of products can lead to ,'self-catabolite repression" (11). These concepts are supported by physiological observations but to our knowledge have not been tested before by genetic means with any extracellular depolymerase.…”

Section: Discussionmentioning

confidence: 99%

Impaired induction and self-catabolite repression of extracellular pectate lyase in Erwinia chrysanthemi mutants deficient in oligogalacturonide lyase

Collmer

Bateman

1981

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

The pectate lyase (PL; EC 4.2.2.2) secreted by the plant pathogen Erwinia chrysanthemi is induced and catabolite repressed by different concentrations of its own product, digalacturonic acid 4,5-unsaturated at the nonreducing end [u(GalUA) 2 ]. Both activities of u(GalUA) 2 depend on its cleavage by oligogalacturonide lyase (OGL; EC 4.2.2.6). This intracellular enzyme converts u(GalUA) 2 to the deoxyketuronic acid 4-deoxy-L- threo -5-hexosulose uronic acid, which is then isomerized to 3-deoxy-D- glycero -2,5-hexodiulosonic acid. An OGL-deficient mutant unable to grow on u(GalUA) 2 was poorly induced by u(GalUA) 2 or by D-galacturonan but produced wild-type levels of PL when supplied with 3-deoxy-D- glycero -2,5-hexodiulosonic acid. PL synthesis in the mutant could also be stimulated by 4,5-unsaturated trigalacturonic acid, from which deoxyketuronic acid is released by another intracellular enzyme. An OGL-deficient mutant that grew slowly on u(GalUA) 2 in comparison with the wild-type parent was hyperinduced by u(GalUA) 2 unless catabolite repression was relieved by cyclic AMP or imposed by logarithmic growth on glycerol. PL synthesis is also stimulated by saturated digalacturonic acid, which is released from D-galacturonan by another extracellular enzyme, exo-poly-α-D-galacturonosidase (EC 3.2.1.82). Because these dimers stimulate PL synthesis at concentrations (wt/vol) 1/1000th of the concentration required by D-galacturonan, and because an OGL-deficient mutant uninducible by dimers was also uninducible by D-galacturonan, we postulate that PL induction by pectic polymers entails extracellular formation of dimers and subsequent intracellular conversion to deoxyketuronic acids, the apparent inducers of PL.

show abstract

Section: Discussionmentioning

confidence: 99%

Impaired induction and self-catabolite repression of extracellular pectate lyase in Erwinia chrysanthemi mutants deficient in oligogalacturonide lyase

Collmer

Bateman

1981

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…The mesophile B. licheniformis and the thermophile B. stearothermophilus produce amylases which are active at temperatures in excess of 75°C (7). It is therefore of interest to determine their primary structures and compare them with each other and with those known for other amylases to ascertain which sequences are associated with the unusual thermophilicity of these enzymes.…”

mentioning

confidence: 99%

Structural genes encoding the thermophilic alpha-amylases of Bacillus stearothermophilus and Bacillus licheniformis

Gray¹,

Mainzer²,

Rey³

et al. 1986

J Bacteriol

View full text Add to dashboard Cite

The genes encoding the thermostable a-amylases of Bacillus stearothermophilus and Bl. licheniformis were cloned in Escherichia coli, and their DNA sequences were determined. The coding and deduced polypeptide sequences are 59 and 62% homologous to each other, respectively. The B. stearothermophilus protein differs most significantly from that of B. licheniformis in that it possesses a 32-residue COOH-terminal tail. Transformation of E. coli with vectors containing either gene resulted in the synthesis and secretion of active enzymes similar to those produced by the parental organisms. A plasmid was constructed in which the promoter and the NH2-terminal two-thirds of the B. stearothermophilus coding sequence was fused out of frame to the entire mature coding sequence of the B. licheniformis gene. Approximately 1 in 5,000 colonies transformed with this plasmid was found to secrete an active amylase. Hybridization analysis of plasmids isolated from these amylase-positive colonies indicated that the parental coding sequences had recombined by homologous recombination. DNA sequeince analysis of selected hybrid genes revealed symmetrical, nonraudom distribution of loci at which the crossovers had resolved. Several purified hybrid ec-amylases were characterized and found to differ with respect to thermostability and specific activity.The ax-amylases secreted by a variety of Bacillus species have been intensively studied. Ihterest has been focused on their mode of secretion, regulation of synthesis, protein structure, and industrial applications. In recent years, the amylase genes of B. coagulans (4) The mesophile B. licheniformis and the thermophile B. stearothermophilus produce amylases which are active at temperatures in excess of 75°C (7). It is therefore of interest to determine their primary structures and compare them with each other and with those known for other amylases to ascertain which sequences are associated with the unusual thermophilicity of these enzymes. In this study we showed that the B. stearothermophilus and B. licheniformis enzymes differ markedly in their specific activities and thermostabilities. Primary structure analysis might also offer clues to these differences.It has been known for some time that the mesophilic amylase of B. amyloliquefaciens has considerable amino acid homology with the B. licheniformis amylase but no homology to the B. subtilis enzyme (21). Recently, comparison of the B. stearothermophilus and B. amyloliquefaciens primary structures has revealed that these proteins are also evolutionarily related (16). In addition, strong similarities between the restriction endonuclease cleavage maps of the amylase genes of B. coagulans and B. licheniformis indicate that these genes may also show homology (21).Since DNA sequence divergence has led to differing chemical properties of the encoded proteins, it is expected that further diversity in this enzyme family might be found in additional natural Bacillus isolates. Alternatively, methods to generate amylase DNA sequence divergence i...

show abstract

“…The optimum working pH range is reported to be from 2 [2] to 10.5 [11] for α-amylase, the other two being in a narrower range. As for the temperature, again α-amylases are active in a broad range or temperature from 20 [12] to 145°C [13].…”

Section: Amylasementioning

confidence: 99%

Enzyme Dynamic in Plant Nutrition Uptake and Plant Nutrition

Turan¹,

Nikerel²,

Kaya³

et al. 2017

Enzyme Inhibitors and Activators

View full text Add to dashboard Cite

Soil contains enzymes, constantly interacting with soil constituents, e.g. minerals, rhizosphere and numerous nutrients. Enzymes, in turn, catalyse important biochemical reactions for rhizobacteria and plants, stabilize the soil by degrading wastes and mediate nutrient recycling.The available enzymes inside soil could originate from plants, animals or microbes. The enzymes that are produced from these organism could exhibit intracellular activities, at the cell membrane, interacting therefore with soil and its constituents, or extracellularly (so freely available). Therefore, vis-à-vis to plant nutrition, the (extra or sub) cellular localization has a key role. Typical major enzymes available in soil can be listed as dehydrogenases, hydrogenases, oxidases, catalases, peroxidases, phenol o-hydroxylase, dextransucrase, aminotransferase, rhodanese, carboxylesterase, lipase, phosphatase, nuclease, phytase, arylsulphatase, amylase, cellulase, inulase, xylanase, dextranase, levanase, poly-galacturonase, glucosidase, galactosidase, invertase, peptidase, asparaginase, glutaminase, amidase, urease, aspartate decarboxylase, glutamate decarboxylase and aromatic amino acid decarboxylase. An interesting strategy for improving the nutritional quality of the soil would be to inoculate microorganism to soil while giving attention to mineral or other compounds that affect enzyme activity in soil. Since, some elements or compounds could show both activation and inhibitory effect, such as Fe, Na, etc. metals, the regulation of their bioavailability is crucial.

show abstract

Bacterial α-Amylases

Cited by 52 publications

References 105 publications

Impaired induction and self-catabolite repression of extracellular pectate lyase in Erwinia chrysanthemi mutants deficient in oligogalacturonide lyase

Impaired induction and self-catabolite repression of extracellular pectate lyase in Erwinia chrysanthemi mutants deficient in oligogalacturonide lyase

Structural genes encoding the thermophilic alpha-amylases of Bacillus stearothermophilus and Bacillus licheniformis

Enzyme Dynamic in Plant Nutrition Uptake and Plant Nutrition

Contact Info

Product

Resources

About