Characterization of SPβ: a temperate bacteriophage from Bacillus subtilis 168M

1977 ◽  
Vol 23 (1) ◽  
pp. 45-51 ◽  
Author(s):  
Fred D. Warner ◽  
Gary A. Kitos ◽  
Martin P. Romano ◽  
H. Ernest Hemphill
Keyword(s):  
Molecular Weight ◽  
Bacillus Subtilis ◽  
Mitomycin C ◽  
Temperate Bacteriophage ◽  
Low Levels

Bacillus subtilis 168M is lysogenic for a temperate bacteriophage called SPβ. The virus head is 76 m wide by 82 m long and the tail measures 12 by 358 m. The DNA molecular weight is 62 million. SPβ is spontaneously released at low levels in cultures of B. subtilis 168M, and can be induced at higher levels by treatment with mitomycin C or N-methyl-N′-nitro-N-nitroso-guanidine.

scholarly journals Characterization of Trypsin Inhibitor in Florunner Peanut Seeds (Arachis hypogaea L.)1

1988 ◽  
Vol 15 (2) ◽  
pp. 81-84 ◽  
Author(s):  
E. M. Ahmed ◽  
J. A. Applewhite
Keyword(s):  
Molecular Weight ◽  
Amino Acid ◽  
Aspartic Acid ◽  
Arachis Hypogaea ◽  
Trypsin Inhibitor ◽  
Low Molecular Weight ◽  
Arachis Hypogaea L ◽  
Amino Acid Profiles ◽  
Low Levels

Abstract Florunner peanut seeds contained five trypsin isoinhibitors. Amino acid profiles of the trypsin inhibitors fraction showed high levels of aspartic acid, half-cystine and serine and low levels of histidine and tyrosine. The molecular weight of the inhibitor was 8.3 KDa. The presence of multiforms of this inhibitor, its low molecular weight and the high amount of half-cystine indicate that peanut trypsin inhibitor is of the Bowman-Birk type.

Characteristic Ratio and Plateau Modulus of 1,2-Polybutadiene. A Comparison with Other Rubbers

1990 ◽  
Vol 63 (5) ◽  
pp. 734-746 ◽  
Author(s):  
Jacques Roovers ◽  
Paul M. Toporowski
Keyword(s):  
Molecular Weight ◽  
Star Polymer ◽  
Dilute Solution ◽  
Plateau Modulus ◽  
Characteristic Ratio ◽  
Polymer Systems ◽  
Dilute Solution Properties ◽  
Linear Viscoelastic ◽  
Low Levels

Abstract In the course of work on linear and ring polybutadienes with 62% 1,2 units, a number of discrepancies were noted with data on polybutadienes of various microstructure available in the literature. For example, GNο=870 kPa for our 62% 1,2-polybutadiene. This is larger than GNο=730 kPa for a 56% 1,2-polybutadiene and GNο=550 kPa for a 78% 1,2-polybutadiene sample. The cis : trans ratio of our 62% 1,2-polybutadiene, prepared with potassium counterion, is 1 : 4, On the other hand, the cis : trans ratio of 62% 1,2-polybutadiene prepared with a modified Li catalyst is estimated to be 1 : 2. It is conceivable that the different cis : trans ratio leads to different properties at constant 1,2 content. Nevertheless, the low levels of both the cis and the trans units are not expected to cause more than minor differences in the properties of the polybutadienes. Correct values for GNο of model polymers are important for the study of the influence of the chemical structure on the melt characteristics of a polymer. For this reason, it was thought useful to reinvestigate 1,2-polybutadiene itself in some detail. The synthesis of narrow molecular-weight distribution 1,2-polybutadiene by anionic polymerization techniques has been described recently. The dilute-solution properties of 1,2-polybutadiene has been investigated. The melt rheology of two 1,2-polybutadiene samples have been studied, but no systematic study of the molecular-weight dependence of the melt properties was made. 1,2-Polybutadiene has been used as a component in block copolymers with 1,4-polybutadiene. These studies have permitted an investigation of the phase behavior of two rubbery blocks at room temperature. Poly(l,4-butadiene-graft-l,2-butadiene)s with well-defined composition and architecture have also been prepared. Hydrosilylated 1,2-polybutadiene has found use as the coupling agent for multiarm star polymer, and this method can easily be extended to the preparation of poly( l,2-butadiene-graft-l,4-butadiene). Hydrogenated 1,2-polybutadienes are prepared as model polymers for poly(l-butene). The synthesis and characterization of a series of 1,2-polybutadienes are described here. Special attention is given to low-molecular-weight polymers. The linear viscoelastic properties of the melts are also described. In the discussion, the relation between the characteristic ratio, C∞, and the plateau modulus, GNο, of a number of model polymer systems is explored.

Purification and characterization of catalase-1 from Bacillus subtilis

1987 ◽  
Vol 65 (11) ◽  
pp. 939-947 ◽  
Author(s):  
Peter C. Loewen ◽  
Jacek Switala
Keyword(s):  
Hydrogen Peroxide ◽  
Molecular Weight ◽  
Bacillus Subtilis ◽  
Amino Acid ◽  
Catalase Activity ◽  
Purification And Characterization ◽  
Ph Range ◽  
Sulfhydryl Compounds ◽  
Native Molecular Weight

The catalase activity produced in vegetative Bacillus subtilis, catalase-1, has been purified to homogeneity. The apparent native molecular weight was determined to be 395 000. Only one subunit type with a molecular weight of 65 000 was present, suggesting a hexamer structure for the enzyme. In other respects, catalase-1 was a typical catalase. Protoheme IX was identified as the heme component on the basis of the spectra of the enzyme and of the isolated hemochromogen. The ratio of protoheme/subunit was 1. The enzyme remained active over a broad pH range of 5–11 and was only slowly inactivated at 65 °C. It was inhibited by cyanide, azide, and various sulfhydryl compounds. The apparent Km for hydrogen peroxide was 40.1 mM. The amino acid composition was typical of other catalases in having relatively low amounts of tryptophan and cysteine.

Characterization of a new efficient low molecular weight Bacillus subtilis NRC 16 levansucrase and its levan

2019 ◽  
Vol 59 (10) ◽  
pp. 1004-1015 ◽  
Author(s):  
Bassem M. Salama ◽  
Wafaa A. Helmy ◽  
Tamer I. M. Ragab ◽  
Mamdouh M. Ali ◽  
Hanan A. A. Taie ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Bacillus Subtilis ◽  
Low Molecular Weight

scholarly journals Expression and characterization of recombinant trehalose synthase in Bacillus subtilis

2020 ◽  
Vol 42 (4) ◽  
Author(s):  
Nguyen Ngoc Trieu ◽  
Nguyen Thi Quynh ◽  
Nguyen Duc Hoang ◽  
Nguyen Manh Dat ◽  
Tran Duc Long ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Monoclonal Antibody ◽  
Bacillus Subtilis ◽  
Specific Activity ◽  
Optimal Conditions ◽  
Trehalose Synthase ◽  
Optimal Activity ◽  
His Tag ◽  
C Terminus

Trehalose synthase (TreS, EC 2.4.1.245) is a potential catalyst for synthesis of trehalose, an important natural disaccharide. In this study, the treS gene of Pseudomonas putida (VTCC 12263) was cloned into pHT01 plasmid at BamHI-XbaI position, expressed in Bacillus subtilis (B. subtilis) 1012, and characterized. The recombinant TreS had molecular weight of 68 kDa when fused with 8xHis tag at the C-terminus. catalyzed conversion of maltose to trehalose in optimal conditions had specific activity of 1.664 U/g. Expression of TreS was highest when B. subtilis 1012 harboring pHT01-treS was cultured in TB medium at 30 oC, induced with 1.0 mM IPTG when OD600 reached 0.8 and harvested after 10 hours of induction. The recombinant TreS purified by Ni-sepharose chromatography had specific activity of 41.700 U/g and formed a single band on Western blot with monoclonal antibody against His-tag. The recombinant TreS had optimal activity at 37 oC in 100 mM pH 7.4 PBS and 300 mM maltose. It was inhibited by NaCl, KCl and MgCl2 (retaining 45% or 75% specific activity in buffer containing 5 mM KCl or 5 mM MgCl2, respectively) and stimulated by imidazol (with specific activity increasing by 30–200%).

scholarly journals Characterization of dacC, Which Encodes a New Low-Molecular-Weight Penicillin-Binding Protein in Bacillus subtilis

1998 ◽  
Vol 180 (18) ◽  
pp. 4967-4973 ◽  
Author(s):  
Lotte B. Pedersen ◽  
Thomas Murray ◽  
David L. Popham ◽  
Peter Setlow
Keyword(s):  
Molecular Weight ◽  
Bacillus Subtilis ◽  
Binding Protein ◽  
Low Molecular Weight ◽  
Penicillin Binding Protein ◽  
Wild Type ◽  
Genome Sequencing Project ◽  
Penicillin Binding Proteins ◽  
Sequencing Project

ABSTRACT The pbp gene (renamed dacC), identified by the Bacillus subtilis genome sequencing project, encodes a putative 491-residue protein with sequence homology to low-molecular-weight penicillin-binding proteins. Use of a transcriptional dacC-lacZ fusion revealed thatdacC expression (i) is initiated at the end of stationary phase; (ii) depends strongly on transcription factor ςH; and (iii) appears to be initiated from a promoter located immediately upstream of yoxA, a gene of unknown function located upstream of dacC on the B. subtilis chromosome. A B. subtilis dacCinsertional mutant grew and sporulated identically to wild-type cells, and dacC and wild-type spores had the same heat resistance, cortex structure, and germination and outgrowth kinetics. Expression ofdacC in Escherichia coli showed that this gene encodes an ∼59-kDa membrane-associated penicillin-binding protein which is highly toxic when overexpressed.

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