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Gonabadi E, Samadlouie HR, Shafafi Zenoozian M. Optimization of culture conditions for enhanced Dunaliella salina productions in mixotrophic culture. Prep Biochem Biotechnol 2021; 52:154-162. [PMID: 34057884 DOI: 10.1080/10826068.2021.1922917] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Dunaliella salina (D. salina) is a green microalga known for its tendency to produce lipid and β-carotene. Fatty acid profile, lipid and β-carotene productions of the microalga D. salina cultivated under different mixotrophic conditions were assayed. Notably, in spite of a broad spectrum of substrates served, mixotrophic cultivations slightly affected the fatty acid composition, and as a result C16:0 and C18:0, C18:1, C18:2 and C18:3 were identified as main fatty acids. Lipid in dry weight biomass (DWB) hit a high of 24.3% at 5% of NaCL and linolenic acid in lipid reached a peak of 9.15% at 15% of NaCL in medium containing glucose and equal amounts of yeast extract and soy bean powder. One-factor-at-a-time was applied to elucidate the substrates which had noticeable impacts on β-carotene production. Glucose, meat peptone, titanium dioxide nanoparticles (TiO2 NPs), pH 7.5 and 5% NaCL were identified as key process parameters impacting β-carotene production. Following, the concentration of glucose, meat peptone and TiO2 NPs were optimized by using response surface method. The highest content of β-carotene, 25.23 mg/g DWB, was obtained in medium composed of (g/L); 22.92 glucose, 5 meat peptone and 0.002 TiO2 NPs.
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Affiliation(s)
- Ebrahim Gonabadi
- Department of Food Science and Technology, Islamic Azad University, Sabzevar Branch, Sabzevar, Iran
| | - Hamid Reza Samadlouie
- Department of Food Science and Technology, Faculty of Agriculture, Shahrood University of Technology, Shahrood, Iran
| | - Masoud Shafafi Zenoozian
- Department of Food Science and Technology, Islamic Azad University, Sabzevar Branch, Sabzevar, Iran
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Gharib-Naseri K, Dorigam JCP, Doranalli K, Morgan N, Swick RA, Choct M, Wu SB. Bacillus amyloliquefaciens CECT 5940 improves performance and gut function in broilers fed different levels of protein and/or under necrotic enteritis challenge. ANIMAL NUTRITION (ZHONGGUO XU MU SHOU YI XUE HUI) 2021; 7:185-197. [PMID: 33997347 PMCID: PMC8110864 DOI: 10.1016/j.aninu.2020.05.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 05/08/2020] [Accepted: 05/13/2020] [Indexed: 11/24/2022]
Abstract
Two studies were conducted to investigate the effect of Bacillus amyloliquefaciens CECT 5940 (BA) as a probiotic on growth performance, amino acid digestibility and bacteria population in broiler chickens under a subclinical necrotic enteritis (NE) challenge and/or fed diets with different levels of crude protein (CP). Both studies consisted of a 2 × 2 factorial arrangement of treatments with 480 Ross 308 mix-sexed broiler chickens. In study 1, treatments included 1) NE challenge (+/-), and 2) BA (1.0 × 106 CFU/g of feed) supplementation (+/-). In study 2, all birds were under NE challenge, and treatments were 1) CP level (Standard/Reduced [2% less than standard]) and 2) BA (1.0 × 106 CFU/g of feed) supplementation (+/-). After inducing NE infection, blood samples were taken on d 16 for uric acid evaluation, and cecal samples were collected for bacterial enumeration. In both studies, ileal digesta was collected on d 35 for nutrient digestibility evaluation. In study 1, the NE challenge reduced body weight gain (BWG), supressed feed conversion ratio (FCR) and serum uric acid levels (P < 0.001). Supplementation of BA increased BWG (P < 0.001) and reduced FCR (P = 0.043) across dietary treatments, regardless of challenge. Bacillus (P = 0.030) and Ruminococcus (P = 0.029) genomic DNA copy numbers and concentration of butyrate (P = 0.017) were higher in birds fed the diets supplemented with BA. In study 2, reduced protein (RCP) diets decreased BWG (P = 0.010) and uric acid levels in serum (P < 0.001). Supplementation of BA improved BWG (P = 0.001) and FCR (P = 0.005) and increased Ruminococcus numbers (P = 0.018) and butyrate concentration (P = 0.033) in the ceca, regardless of dietary CP level. Further, addition of BA reduced Clostridium perfringens numbers only in birds fed with RCP diets (P = 0.039). At d 35, BA supplemented diets showed higher apparent ileal digestibility of cystine (P = 0.013), valine (P = 0.020), and lysine (P = 0.014). In conclusion, this study suggests positive effects of BA supplementation in broiler diets via modulating gut microflora and improving nutrient uptake.
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Affiliation(s)
- Kosar Gharib-Naseri
- School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia
| | - Juliano C P Dorigam
- Evonik Nutrition & Care GmbH, Rodenbacher Chaussee 4, 63457 Hanau-Wolfgang, Germany
| | - Kiran Doranalli
- Evonik Nutrition & Care GmbH, Rodenbacher Chaussee 4, 63457 Hanau-Wolfgang, Germany
| | - Natalie Morgan
- School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia
| | - Robert A Swick
- School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia
| | - Mingan Choct
- University of New England, Armidale 2351, Australia
| | - Shu-Biao Wu
- School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia
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Draft Genome Sequence of the Industrially Significant Bacterium Bacillus amyloliquefaciens NRRL 942. Microbiol Resour Announc 2018; 7:MRA01374-18. [PMID: 30533784 PMCID: PMC6256549 DOI: 10.1128/mra.01374-18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 10/14/2018] [Indexed: 11/20/2022] Open
Abstract
Bacillus amyloliquefaciens NRRL 942 is a Gram-positive bacterium with several potential industrial uses. We have sequenced the whole genome of this organism to assist in understanding the biological mechanisms that might modulate human health or environmental risk in the event of its release into the environment.
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Samadlouie HR, Nurmohamadi S, Moradpoor F, Gharanjik S. Effect of low-cost substrate on the fatty acid profiles of Mortierella alpina CBS 754.68 and Wickerhamomyces siamensis SAKSG. BIOTECHNOL BIOTEC EQ 2018. [DOI: 10.1080/13102818.2018.1471360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
Affiliation(s)
- Hamid Reza Samadlouie
- Department of Food Science and Technology, Faculty of Agricultural Engineering, Shahrood University of Technology, Shahrood, Iran
| | - Sanaz Nurmohamadi
- Department of Food Science and Technology, Faculty of Agricultural Engineering, Ayat Ollah Amoli Branch, Islamic Azad University, Amol, Iran
| | - Fatemeh Moradpoor
- Department of Food Science and Technology, Faculty of Agricultural Engineering, Ayat Ollah Amoli Branch, Islamic Azad University, Amol, Iran
| | - Shahrokh Gharanjik
- Department of Biotechnology, Faculty of Agricultural Engineering, Shahrood University of Technology, Shahrood, Iran
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Khademy M, Karimi B, Zareian S. Ionic Liquid-Based Periodic Mesoporous Organosilica: An Innovative Matrix for Enzyme Immobilization. ChemistrySelect 2017. [DOI: 10.1002/slct.201701710] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Mitra Khademy
- Department of Biological Sciences; Institute for Advanced Studies in Basic Sciences; 444 Gava-zang Zanjan 45137-6731 Iran
| | - Babak Karimi
- Department of Chemistry; Institute for Advanced Studies in Basic Sciences; PO-Box 45195-1159, Gava-zang Zanjan 45137-6731 Iran
| | - Shekufeh Zareian
- Department of Biological Sciences; Institute for Advanced Studies in Basic Sciences; 444 Gava-zang Zanjan 45137-6731 Iran
- Division of Biology and Biological Engineering; California Institute of technology; 1200 E California Blvd Pasadena, CA 91125
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Claisse G, Feller G, Bonneau M, Da Lage JL. A single amino-acid substitution toggles chloride dependence of the alpha-amylase paralog amyrel in Drosophila melanogaster and Drosophila virilis species. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2016; 75:70-77. [PMID: 27312592 DOI: 10.1016/j.ibmb.2016.06.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 06/01/2016] [Accepted: 06/10/2016] [Indexed: 06/06/2023]
Abstract
In animals, most α-amylases are chloride-dependent enzymes. A chloride ion is required for allosteric activation and is coordinated by one asparagine and two arginine side chains. Whereas the asparagine and one arginine are strictly conserved, the main chloride binding arginine is replaced by a glutamine in some rare instances, resulting in the loss of chloride binding and activation. Amyrel is a distant paralogue of α-amylase in Diptera, which was not characterized biochemically to date. Amyrel shows both substitutions depending on the species. In Drosophila melanogaster, an arginine is present in the sequence but in Drosophila virilis, a glutamine occurs at this position. We have investigated basic enzymological parameters and the dependence to chloride of Amyrel of both species, produced in yeast, and in mutants substituting arginine to glutamine or glutamine to arginine. We found that the amylolytic activity of Amyrel is about thirty times weaker than the classical Drosophila α-amylase, and that the substitution of the arginine by a glutamine in D. melanogaster suppressed the chloride-dependence but was detrimental to activity. In contrast, changing the glutamine into an arginine rendered D. virilis Amyrel chloride-dependent, and interestingly, significantly increased its catalytic efficiency. These results show that the chloride ion is not mandatory for Amyrel but stimulates the reaction rate. The possible phylogenetic origin of the arginine/glutamine substitution is also discussed.
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Affiliation(s)
- Gaëlle Claisse
- UMR 9191 Evolution, Génomes, Comportement et Ecologie, CNRS, F-91198 Gif-sur-Yvette, France; Univ. Paris-Sud, F-91405 Orsay Cedex, France
| | - Georges Feller
- Laboratory of Biochemistry, Center for Protein Engineering, University of Liège, B-4000 Liège-Sart Tilman, Belgium
| | - Magalie Bonneau
- UMR 9191 Evolution, Génomes, Comportement et Ecologie, CNRS, F-91198 Gif-sur-Yvette, France; Univ. Paris-Sud, F-91405 Orsay Cedex, France
| | - Jean-Luc Da Lage
- UMR 9191 Evolution, Génomes, Comportement et Ecologie, CNRS, F-91198 Gif-sur-Yvette, France; Univ. Paris-Sud, F-91405 Orsay Cedex, France.
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Yoo YJ, Hong J, Hatch RT. Comparison of alpha-amylase activities from different assay methods. Biotechnol Bioeng 2012; 30:147-51. [PMID: 18576594 DOI: 10.1002/bit.260300120] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Y J Yoo
- Department of Chemical Engineering, University of Maryland, College Park, Maryland 20742
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Alikhajeh J, Khajeh K, Ranjbar B, Naderi-Manesh H, Lin YH, Liu E, Guan HH, Hsieh YC, Chuankhayan P, Huang YC, Jeyaraman J, Liu MY, Chen CJ. Structure of Bacillus amyloliquefaciens alpha-amylase at high resolution: implications for thermal stability. Acta Crystallogr Sect F Struct Biol Cryst Commun 2010; 66:121-9. [PMID: 20124706 PMCID: PMC2815676 DOI: 10.1107/s1744309109051938] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2009] [Accepted: 12/02/2009] [Indexed: 11/10/2022]
Abstract
The crystal structure of Bacillus amyloliquefaciens alpha-amylase (BAA) at 1.4 A resolution revealed ambiguities in the thermal adaptation of homologous proteins in this family. The final model of BAA is composed of two molecules in a back-to-back orientation, which is likely to be a consequence of crystal packing. Despite a high degree of identity, comparison of the structure of BAA with those of other liquefying-type alpha-amylases indicated moderate discrepancies at the secondary-structural level. Moreover, a domain-displacement survey using anisotropic B-factor and domain-motion analyses implied a significant contribution of domain B to the total flexibility of BAA, while visual inspection of the structure superimposed with that of B. licheniformis alpha-amylase (BLA) indicated higher flexibility of the latter in the central domain A. Therefore, it is suggested that domain B may play an important role in liquefying alpha-amylases, as its rigidity offers a substantial improvement in thermostability in BLA compared with BAA.
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Affiliation(s)
- Jahan Alikhajeh
- Life Science Group, Scientific Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
- Department of Biochemistry, Faculty of Science, Tarbiat Modares University, Tehran, Iran
| | - Khosro Khajeh
- Department of Biochemistry, Faculty of Science, Tarbiat Modares University, Tehran, Iran
| | - Bijan Ranjbar
- Department of Biophysics, Faculty of Science, Tarbiat Modares University, Tehran, Iran
| | - Hossein Naderi-Manesh
- Department of Biophysics, Faculty of Science, Tarbiat Modares University, Tehran, Iran
| | - Yi-Hung Lin
- Life Science Group, Scientific Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Enhung Liu
- Life Science Group, Scientific Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Hong-Hsiang Guan
- Life Science Group, Scientific Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Yin-Cheng Hsieh
- Life Science Group, Scientific Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Phimonphan Chuankhayan
- Life Science Group, Scientific Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Yen-Chieh Huang
- Life Science Group, Scientific Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Jeyakanthan Jeyaraman
- Life Science Group, Scientific Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Ming-Yih Liu
- Life Science Group, Scientific Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
- Institute of Nuclear Energy Research Center, Atomic Energy Council, Taoyuan 32546, Taiwan
| | - Chun-Jung Chen
- Life Science Group, Scientific Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
- Department of Physics, National Tsing Hua University, Hsinchu 30014, Taiwan
- Institute of Biotechnology, National Cheng Kung University, Tainan 70101, Taiwan
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9
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Workman WE, McLinden JH, Dean DH, Copeland JC. Genetic Engineering Applications to Biotechnology in the GenusBacillus. Crit Rev Biotechnol 2008. [DOI: 10.3109/07388558509150784] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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10
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Giraud E, Gosselin L, Marin B, Parada J, Raimbault M. Purification and characterization of an extracellular amylase fromLactobacillus plantarumstrain A6. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1365-2672.1993.tb02777.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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11
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MORGAN FJ, PRIEST FG. Characterization of a Thermostable α-Amylase fromBacillus licheniformisNCIB 6346. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1365-2672.1981.tb00875.x] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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12
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Shirai T, Igarashi K, Ozawa T, Hagihara H, Kobayashi T, Ozaki K, Ito S. Ancestral sequence evolutionary trace and crystal structure analyses of alkaline alpha-amylase from Bacillus sp. KSM-1378 to clarify the alkaline adaptation process of proteins. Proteins 2007; 66:600-10. [PMID: 17154418 DOI: 10.1002/prot.21255] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The crystal structure of alkaline liquefying alpha-amylase (AmyK) from the alkaliphilic Bacillus sp. KSM-1378 was determined at 2.1 A resolution. The AmyK structure belongs to the GH13 glycoside hydrolase family, which consists of three domains, and bound three calcium and one sodium ions. The alkaline adaptation mechanism of AmyK was investigated by the ancestral sequence evolutionary trace method and by extensive comparisons between alkaline and nonalkaline enzyme structures, including three other protein families: protease, cellulase, and phosphoserine aminotransferase. The consensus change for the alkaline adaptation process was a decrease in the Lys content. The loss of a Lys residue is associated with ion pair remodeling, which mainly consists of the loss of Lys-Asp/Glu ion pairs and the acquisition of Arg ion pairs, preferably Arg-Glu. The predicted replacements of the positively charged amino acids were often, although not always, used for ion pair remodeling.
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Affiliation(s)
- Tsuyoshi Shirai
- Department of Bioscience, Nagahama Institute of Bio-science and Technology, Nagahama 526-0829, Japan.
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Giraud E, Cuny G. Molecular characterization of the alpha-amylase genes of Lactobacillus plantarum A6 and Lactobacillus amylovorus reveals an unusual 3' end structure with direct tandem repeats and suggests a common evolutionary origin. Gene 1997; 198:149-57. [PMID: 9370276 DOI: 10.1016/s0378-1119(97)00309-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The alpha-amylase gene (amyA) of Lactobacillus plantarum A6 was isolated from the genome by polymerase chain reaction with degenerated oligonucleotides, synthesized according to the tryptic peptide amino acid sequences of the purified enzyme. Nucleic acid sequence analysis revealed one open reading frame of 2739 bp encoding a 913 amino acid protein. The amylase appears to be divided into two equal parts. The N-terminal part has the typical characteristics of the well-known alpha-amylase family (65% identity with the alpha-amylase of Bacillus subtilis and 97% identity with the partial sequence available for the alpha-amylase of Lactobacillus amylovorus). The C-terminal part displays a fairly unusual structure. It consists of four direct tandem repeated sequences of 104 amino acids sharing 100% similarity. The complete nucleotide sequence of the alpha-amylase gene of L. amylovorus was also determined. An open reading frame of 2862 bp encoding a 954 amino acid protein was identified. Perfect homology between the two amyA genes was observed in the N-terminal region. The C-terminal part of L. amylovorus alpha-amylase also included tandem repeat units but striking differences were observed: (i) the addition of one repeat unit; (ii) a shorter, 91 amino acid repetition unit. These structural homologies suggest that both genes have a common ancestor and may have evolved independently by duplication with subsequent recombination and mutation.
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Affiliation(s)
- E Giraud
- Laboratoire de Biotechnologie, ORSTOM, Montpellier, France.
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Mathur S, Cannistraro VJ, Kennell D. Identification of an intracellular pyrimidine-specific endoribonuclease from Bacillus subtilis. J Bacteriol 1993; 175:6717-20. [PMID: 8407848 PMCID: PMC206785 DOI: 10.1128/jb.175.20.6717-6720.1993] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Two intracellular RNases which were easily separated by fractionation on strong anion- or cation-exchange resins were identified from Bacillus subtilis. One cleaved any phosphodiester bond, while the second cleaved only pyrimidine-N bonds. The enzyme with pyrimidine-N specificity was approximately 15 kDa, had a pH optimum of approximately 6.2, degraded C-C bonds approximately 10 times faster than U-U bonds, and was completely inactive against single-stranded DNA. The enzyme is called RNase C and may be the first reported broad-specificity endoribonuclease from B. subtilis.
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Affiliation(s)
- S Mathur
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri 63110
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15
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Emori M, Takagi M, Maruo B, Yano K. Molecular cloning, nucleotide sequencing, and expression of the Bacillus subtilis (natto) IAM1212 alpha-amylase gene, which encodes an alpha-amylase structurally similar to but enzymatically distinct from that of B. subtilis 2633. J Bacteriol 1990; 172:4901-8. [PMID: 2118504 PMCID: PMC213144 DOI: 10.1128/jb.172.9.4901-4908.1990] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
An alpha-amylase gene of Bacillus subtilis (natto) IAM1212 was cloned in a lambda EMBL3 bacteriophage vector, and the nucleotide sequence was determined. An open reading frame encoding the alpha-amylase (AMY1212) consists of 1,431 base pairs and contains 477 amino acid residues, which is the same in size as the alpha-amylase (AMY2633) of B. subtilis 2633, an alpha-amylase-hyperproducing strain, and smaller than that of B. subtilis 168, Marburg strain. The amino acid sequence of AMY1212 is different from that of AMY2633 at five residues. Enzymatic properties of these two alpha-amylases were examined by introducing the cloned genes into an alpha-amylase-deficient strain, B. subtilis M15. It was revealed that products of soluble starch hydrolyzed by AMY1212 are maltose and maltotriose, while those of AMY2633 are glucose and maltose. From the detailed analyses with oligosaccharides as substrates, it was concluded that the difference in hydrolysis products of the two similar alpha-amylases should be ascribed to the different activity hydrolyzing low-molecular-weight substrates, especially maltotriose; AMY1212 slowly hydrolyzes maltotetraose and cannot hydrolyze maltotriose, while AMY2633 efficiently hydrolyzes maltotetraose and maltotriose. Further analyses with chimeric alpha-amylase molecules constructed from the cloned genes revealed that only one amino acid substitution is responsible for the differences in hydrolysis products.
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Affiliation(s)
- M Emori
- Laboratory of Radiation Microbiology, Faculty of Agriculture, University of Tokyo, Japan
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Abstract
Starch-degrading, amylolytic enzymes are widely distributed among microbes. Several activities are required to hydrolyze starch to its glucose units. These enzymes include alpha-amylase, beta-amylase, glucoamylase, alpha-glucosidase, pullulan-degrading enzymes, exoacting enzymes yielding alpha-type endproducts, and cyclodextrin glycosyltransferase. Properties of these enzymes vary and are somewhat linked to the environmental circumstances of the producing organisms. Features of the enzymes, their action patterns, physicochemical properties, occurrence, genetics, and results obtained from cloning of the genes are described. Among all the amylolytic enzymes, the genetics of alpha-amylase in Bacillus subtilis are best known. Alpha-Amylase production in B. subtilis is regulated by several genetic elements, many of which have synergistic effects. Genes encoding enzymes from all the amylolytic enzyme groups dealt with here have been cloned, and the sequences have been found to contain some highly conserved regions thought to be essential for their action and/or structure. Glucoamylase appears usually in several forms, which seem to be the results of a variety of mechanisms, including heterogeneous glycosylation, limited proteolysis, multiple modes of mRNA splicing, and the presence of several structural genes.
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Affiliation(s)
- M Vihinen
- Department of Biochemistry, University of Turku, Finland
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18
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Chu Yuan Cheng, Yabe I, Toda K. Predominant growth of α-amylase regulation mutant in continuous culture of Bacillus caldolyticus. ACTA ACUST UNITED AC 1989. [DOI: 10.1016/0922-338x(89)90118-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Pretorius IS, Laing E, Pretorius GH, Marmur J. Expression of a Bacillus alpha-amylase gene in yeast. Curr Genet 1988; 14:1-8. [PMID: 2843299 DOI: 10.1007/bf00405846] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A recombinant plasmid, pSR11.3, containing the alpha-amylase gene (AMY) of Bacillus amyloliquefaciens was characterized and expressed in Bacillus subtilis. A 2.3 kilobase BamHI-BglII fragment carrying AMY was cloned into pBR322 (pEL322) and in both orientations into a multi-copy Escherichia coli-yeast shuttle vector YEp13 (pAM13) and expressed in E. coli HB101 and various Saccharomyces stains. We report on the successful secretion of an active bacterial enzyme in yeast without using yeast promoter and secretory signals. Enzyme production in B. subtilis 1A297(pSR11.3), E. coli HB101(pEL322) and Saccharomyces JM2773-15B(pAM13) transformants was measured as 125, 22 and 123 U/ml, respectively. The molecular weight of the purified alpha-amylase secreted by B. subtilis 1A297(pSR11.3) and Saccharomyces JM2773-15B-(pAM13) was estimated to be 55 kDa. The pH and temperature optima for the alpha-amylase activities of the transformants were 6.5 to 8.0 and 50 to 65 degrees C, respectively. Amylose hydrolysis profiles of the alpha-amylases secreted by B. subtilis 1A297(pSR11.3) and Saccharomyces JM2773-15B(pAM13) indicate effective meso-thermostable hydrolytic enzymes with maltotriose and maltose, respectively, as major end products.
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Affiliation(s)
- I S Pretorius
- Department of Microbiology, University of Stellenbosch, South Africa
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21
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Corfield VA, Botes DP, Thomson JA. A molecular approach to the characterization of an industrialBacillus amyloliquefaciens strain. Curr Microbiol 1987. [DOI: 10.1007/bf01588177] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Dias FF, Shaikh MK, Bhatt YB, Modi DC, Subramanyam VR. Tunicamycin-resistant mutants of Bacillus amyloliquefaciens are deficient in amylase, protease and penicillinase synthesis and have altered sensitivity to antibiotics and autolysis. THE JOURNAL OF APPLIED BACTERIOLOGY 1986; 60:271-5. [PMID: 2424885 DOI: 10.1111/j.1365-2672.1986.tb01733.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Mutants of Bacillus amyloliquefaciens resistant to at least 10 micrograms/ml of tunicamycin were isolated and shown to be pleiotropic. The mutants were more resistant to streptomycin, chloramphenicol, kanamycin and neomycin than was the parent strain but less resistant to penicillin G and tetracycline. They were more autolytic, presumably due to an altered cell wall. The mutants produced reduced levels of amylase, penicillinase and both metal and serine protease besides having an enhanced sporulation frequency and being more motile.
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23
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Kochhar S, Dua RD. An active center tryptophan residue in liquefying alpha-amylase from Bacillus amyloliquefaciens. Biochem Biophys Res Commun 1985; 126:966-73. [PMID: 3872124 DOI: 10.1016/0006-291x(85)90280-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Liquefying alpha-amylase from Bacillus amyloliquefaciens was inactivated on treatment with N-bromosuccinamide. Preincubation of the enzyme with either of the substrate, or competitive inhibitor provided significant protection against inactivation. The relationship between activity loss and the number of tryptophan residues modified, as well as presence of substrate/inhibitor in the reaction mixture, demonstrated that only one of three modifiable tryptophan residues is at or near the active center. The apparent Km of the modified enzyme for soluble starch increased manifold, thus implicating the sensitive tryptophan residue in the substrate binding region of the enzyme.
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24
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Krishnan T, Chandra AK. Purification and Characterization of α-Amylase from
Bacillus licheniformis
CUMC305. Appl Environ Microbiol 1983; 46:430-7. [PMID: 16346366 PMCID: PMC239407 DOI: 10.1128/aem.46.2.430-437.1983] [Citation(s) in RCA: 73] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
α-Amylase produced by
Bacillus licheniformis
CUMC305 was purified 212-fold with a 42% yield through a series of four steps. The purified enzyme was homogeneous as shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and discontinuous gel electrophoresis. The purified enzyme showed maximal activity at 90�C and pH 9.0, and 91% of this activity remained at 100�C. The enzyme retained 91, 79, and 71% maximal activity after 3 h of treatment at 60�C, 3 h at 70�C, and 90 min at 80�C, respectively, in the absence of substrate. On the contrary, in the presence of substrate (soluble starch), the α-amylase enzyme was fully stable after a 4-h incubation at 100�C. The enzyme showed 100% stability in the pH range 7 to 9; 95% stability at pH 10; and 84, 74, 68, and 50% stability at pH values of 6, 5, 4, and 3, respectively, after 18 h of treatment. The activation energy for this enzyme was calculated as 5.1 � 10
5
J/mol. The molecular weight was estimated to be 28,000 by sodium dodecyl sulfate-gel electrophoresis. The relative rates of hydrolysis of soluble starch, amylose, amylopectin, and glycogen were 1.27, 1.8, 1.94, and 2.28 mg/ml, respectively.
V
max
values for hydrolysis of these substrates were calculated as 0.738, 1.08, 0.8, and 0.5 mg of maltose/ml per min, respectively. Of the cations, Na
+
, Ca
2+
, and Mg
2+
, showed stimulatory effect, whereas Hg
2+
, Cu
2+
, Ni
2+
, Zn
2+
, Ag
+
, Fe
2+
, Co
2+
, Cd
2+
, Al
3+
, and Mn
2+
were inhibitory. Of the anions, azide, F
−
, SO
3
2−
, SO
4
3−
, S
2
O
3
2−
, MoO
4
2−
, and Wo
4
2−
showed an excitant effect.
p
-Chloromercuribenzoic acid and sodium iodoacetate were inhibitory, whereas cysteine, reduced glutathione, thiourea, β-mercaptoethanol, and sodium glycerophosphate afforded protection to enzyme activity. α-Amylase was fairly resistant to EDTA treatment at 30�C, but heating at 90�C in presence of EDTA resulted in the complete loss of enzyme activity, which could be recovered partially by the addition of Cu
2+
and Fe
2+
but not by the addition of Ca
2+
or any other divalent ions.
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Affiliation(s)
- T Krishnan
- Microbiology Laboratory, Department of Botany, University of Calcutta, Calcutta-700 019, India
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Sibakov M, Sarvas M, Palva I. Increased secretion of α-amylase fromBacillus subtiliscaused by multiple copies of α-amylase gene fromB. amyloliquefaciensis not further increased by genes enhancing the basic level of secretion. FEMS Microbiol Lett 1983. [DOI: 10.1111/j.1574-6968.1983.tb00377.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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26
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Yang M, Galizzi A, Henner D. Nucleotide sequence of the amylase gene from Bacillus subtilis. Nucleic Acids Res 1983; 11:237-49. [PMID: 6186986 PMCID: PMC325711 DOI: 10.1093/nar/11.2.237] [Citation(s) in RCA: 156] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The gene coding for amylase (EC.3.2.1.1) has been isolated and sequenced from Bacillus subtilis by cloning in lambda Charon4A and pBR322. The entire coding sequence and large preceding and following regions, comprising the presumed transcriptional and translational regulatory regions, were sequenced. The coding sequence shows a large open reading frame with a translated molecular weight of 72,800 and a presumed signal sequence of approximately thirty-two amino acids. When the intact gene is present in Escherichia coli, it confers the ability to degrade starch, indicating that the gene is expressed in a functional state.
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27
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Mäntsälä P, Puntala M. Comparison of levansucrase fromBacillus subtilisand fromBacillus amyloliquefaciens. FEMS Microbiol Lett 1982. [DOI: 10.1111/j.1574-6968.1982.tb08294.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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28
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Kuhn H, Fietzek PP, Lampen JO. N-terminal amino acid sequence of Bacillus licheniformis alpha-amylase: comparison with Bacillus amyloliquefaciens and Bacillus subtilis Enzymes. J Bacteriol 1982; 149:372-3. [PMID: 6172418 PMCID: PMC216633 DOI: 10.1128/jb.149.1.372-373.1982] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The thermostable, liquefying alpha-amylase from Bacillus licheniformis was immunologically cross-reactive with the thermolabile, liquefying alpha-amylase from Bacillus amyloliquefaciens. Their N-terminal amino acid sequences showed extensive homology with each other, but not with the saccharifying alpha-amylases of Bacillus subtilis.
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29
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Davis PE, Cohen DL, Whitaker A. The production of alpha-amylase in batch and chemostat culture by Bacillus stearothermophilus. Antonie Van Leeuwenhoek 1980; 46:391-8. [PMID: 6160812 DOI: 10.1007/bf00421985] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The production of alpha-amylase (alpha-1,4-glucan 4-glucanohydrolase; EC 3.2.1.1) by a strain of Bacillus stearothermophilus isolated from leaf litter was investigated in a tryptone-maltose medium at 55 degrees C in batch and chemostat culture. Amylase production was growth-limited and restricted to the exponential phase in batch culture. The enzyme yield was reduced by 40% when the culture pH was maintained at pH 7.2. Amylase production in chemostat culture was influenced by the growth rate throughout the dilution rate range used.
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30
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GRANUM PEREINAR. PURIFICATION AND PHYSICOCHEMICAL PROPERTIES OF AN EXTRA CELLULAR AMYLASE FROM A STRAIN OF BACILLUS AMYLOLIQUEFACIENS ISOLATED FROM DRY ONION POWDER. J Food Biochem 1979. [DOI: 10.1111/j.1745-4514.1979.tb00631.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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31
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Borgia PT, Campbell LL. alpha-amylase from five strains of Bacillus amyloliquefaciens: evidence for identical primary structures. J Bacteriol 1978; 134:389-93. [PMID: 306994 PMCID: PMC222264 DOI: 10.1128/jb.134.2.389-393.1978] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The alpha-amylases from five strains of Bacillus amyloliquefaciens were compared to determine whether differences in primary structure are responsible for variations in catalytic properties previously reported among the enzymes. Amino acid analysis established virtually identical compositions for the proteins. Reaction with dimethylaminoaphthylene sulfonylchloride indicated the amino-terminal amino acid of each amylase to be valine. Carboxyl termini of the enzymes have been determined by digestion with carboxypeptidase A. The resulting kinetic data indicate tyrosine as the carboxyl terminus and leucine as the penultimate residue for all five proteins. Isoelectric focusing of the enzymes yielded isoelectric points in the pH range of 5.09 to 5.18. Tryptic digests of the enzymes chromatographed on a cation-exchange column showed identical elution patterns. It is concluded that the primary structure of the amylase from the five strains is identical or exhibits only conservative substitutions.
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32
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33
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Abstract
Bacillus amyloliquefaciens alpha-amylase was attached to dextran after activation of the polysaccharide by using a modification of the cyanogen bromide method. The soluble dextran-amylase conjugate was purified by molecular-sieve chromatography. The conjugated enzyme has greater stability than the unmodified enzyme at low pH values, during heat treatment, and on removal of calcium ions with a chelating agent. Attachment of dextran to alpha-amylase did not alter the Michaelis constant of the enzyme acting on starch. The polysaccharide-enzyme conjugate probably consists of a cross-linked aggregate of many dextran and many enzyme molecules, in which a proportion of the enzyme molecules, although not inactivated, are unable to express their activity, except after dextranase treatment.
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34
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Marshall JJ, Lauda CM. Purification and properties of phaseolamin, an inhibitor of alpha-amylase, from the kidney bean, Phaseolus vulgaris. J Biol Chem 1975. [DOI: 10.1016/s0021-9258(19)40811-9] [Citation(s) in RCA: 102] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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35
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Abstract
A number of mutants of Bacillus subtilis producing high levels of extracellular protease have been isolated. Analysis of culture supernatants of these mutants has shown that the total amount of proteolytic activity is elevated from 16- to 37-fold over the wild strain. The elevated activity was due to a simultaneous increase in both the neutral and alkaline protease. All of the mutants genetically analyzed were found linked to the argC4 marker by PBS-1 transduction analysis.
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36
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Grant MA, Coleman G. A study of the nature of the immediate precursor of the extracellular -amylase of Bacillus amyloliquefaciens. A reappraisal. Biochem J 1972; 129:483-90. [PMID: 4643331 PMCID: PMC1174098 DOI: 10.1042/bj1290483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
1. A defined medium was devised for use in washed-cell experiments with post-exponential-phase cultures of Bacillus amyloliquefaciens. The medium allowed alpha-amylase to be secreted, bacterial concentration to increase and l-[U-(14)C]valine to be incorporated into protein at a linear rate, which was the same as in a post-exponential-phase culture, for up to 6h. 2. Determination of the specific radioactivity of l-[U-(14)C]valine in the medium, the intracellular amino acid pool, the cellular protein and the isolated alpha-amylase, after a 3h incubation of washed cells in the defined medium, showed that at least 76% of the alpha-amylase secreted was synthesized de novo. 3. By isolating the alpha-amylase formed during a 6h incubation in the presence of l-[U-(14)C]valine it was shown that the specific radioactivity of the N-terminal valine, within the limits of experimental error, was the same as that of the total valine residues from the complete alpha-amylase molecule. 4. A consideration of these results in relation to the whole literature on the subject strongly supports the idea that there is no reason to suppose that extracellular alpha-amylase is formed from a high-molecular-weight precursor in B. amyloliquefaciens and closely related organisms with identical characteristics of exoenzyme secretion.
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37
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May BK, Elliott WH. Synthesis and properties of a protoplast-bursting factor from Bacillus amyloliquefaciens. Biochem Biophys Res Commun 1970; 41:199-205. [PMID: 4989884 DOI: 10.1016/0006-291x(70)90488-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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38
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Moseley MH, Keay L. Purification and characterization of the amylase of B. subtilis NRRL B3411. Biotechnol Bioeng 1970; 12:251-71. [PMID: 4990333 DOI: 10.1002/bit.260120207] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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39
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Coleman G. Effect of the magnesium concentration in the extracting medium on the polyribosome content and the cell-free amino acid incorporating ability of extracts of logarithmic phase cells of a Bacillus sp. BIOCHIMICA ET BIOPHYSICA ACTA 1969; 182:180-92. [PMID: 4978865 DOI: 10.1016/0005-2787(69)90533-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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40
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Coleman G. Effect of potassium ions on the attachment of polyribosomes to the membranes in lysates of exponential-phase cells of Bacillus amyloliquefaciens. Biochem J 1969; 112:533-9. [PMID: 5809217 PMCID: PMC1187744 DOI: 10.1042/bj1120533] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
1. The distribution of ribosomal components between the soluble and membrane fractions of a preparation of exponential-phase cells of Bacillus amyloliquefaciens lysed with lysozyme in 0.05m-tris buffer, pH7.6, containing 0.01m-Mg(2+), was strongly influenced by the addition of K(+) to the buffer, in the range 0-0.1m. 2. In the absence of K(+), 37% of the ribosomal material was bound to the membrane and was not removed by repeated washing with the lysing buffer. The amount of bound material was progressively decreased on increasing the K(+) concentration to 0.1m, when only 5% of ribosomal components remained attached to the membrane. 3. About 87% of the material that remained bound to the washed membranes prepared in the absence of added K(+) was removed on suspension of the membranes in a buffer containing 0.1m-potassium chloride. 4. In the absence of K(+), washed membranes, containing no detectable ribosomal material, were able to re-attach no more than half as much material as was found associated with membranes in the same buffer immediately after lysis. 5. There was no evidence of binding of specific components to the membrane. 6. In the presence of 0.05m-tris buffer, pH7.6, maximum incorporation of amino acids into protein by B. amyloliquefaciens polyribosomes is effected in the presence of 0.01m-Mg(2+) and 0.07-0.1m-K(+), under which conditions less than 10% of the ribosomal material of a cell lysate would be membrane-bound.
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41
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Coleman G. Effect of potassium ion concentration on the cell-free amino acid incorporating ability of polyribosomes isolated from logarithmic phase cells of a Bacillus sp. BIOCHIMICA ET BIOPHYSICA ACTA 1969; 174:395-7. [PMID: 4974835 DOI: 10.1016/0005-2787(69)90265-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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42
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Welker NE, Campbell LL. Crystallization and properties of alpha-amylase from five strains of Bacillus amyloliquefaciens. Biochemistry 1967; 6:3681-9. [PMID: 4965575 DOI: 10.1021/bi00864a010] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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43
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Abstract
Eight strains of highly amylolytic, sporeforming bacilli (hereafter referred to as Bacillus amyloliquefaciens) were compared with respect to their taxonomic relationship to B. subtilis. The physiological-biochemical properties of these two groups of organisms showed that B. amyloliquefaciens differed from B. subtilis by their ability to grow in 10% NaCl, characteristic growth on potato plugs, increased production of alpha-amylase, and their ability to ferment lactose with the production of acid. The base compositions of the deoxyribonucleic acid (DNA) of the B. subtilis strains consistently fell in the range of 41.5 to 43.5% guanine + cytosine (G + C), whereas that of the B. amyloliquefaciens strains was in the 43.5 to 44.9% G + C range. Hybrid formation between B. subtilis W23 and B. amyloliquefaciens F DNA revealed only a 14.7 to 15.4% DNA homology between the two species. Transducing phage, SP-10, was able to propagate on B. subtilis W23 and B. amyloliquefaciens N, and would transduce B. subtilis 168 (indole(-)) and B. amyloliquefaciens N-10 (arginine(-)) to prototrophy with a frequency of 3.9 x 10(-4) and 2.4 x 10(-5) transductants per plaque-forming unit, respectively. Attempts to transduce between the two species were unsuccessful. These data show that Bacillus amyloliquefaciens is a valid species and should not be classified as a strain or variety of B. subtilis.
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