scholarly journals Curly Stem – an Induced Mutation in Flax (Linum usitatissimum L.)

2012 ◽  
Vol 38 (No. 3-4) ◽  
pp. 125-128 ◽  
Author(s):  
E. Tejklová

After ethyl methane sulfonate (EMS) treatment of two flax lines, curly stem mutations appeared in both, besides of other mutations. Genetic analysis of one CS mutant line confirmed a monogenic inheritance of the changed stem shape. The curly stem allele is partially dominant over the wild type allele for straight stem. Homozygotic mutants have a curly stem, heterozygotic plants have a flexuous stem, while the stem of homozygotic recessive plants is straight. The expression of the curly stem character is affected by factors influencing plant growth. The utilisation of this mutation for ornamental and other purposes is considered.

2019 ◽  
Vol 6 (1) ◽  
pp. 20
Author(s):  
Galih Cendana Nabilasani ◽  
Trismilah Siswodarsono ◽  
Dadang Suhendar ◽  
Nisa Rachmania Mubarik

Lipase Production by Mutant Fungal Isolates for Transesterification ABSTRACTLipase is used amongst others in biodiesel production, namely in the transesterification reaction. Kernel B (KB) was a fungus isolated from the waste of palm kernel and seed. The fungus produced lipase that catalysed the transesterification reaction with a lower activity compared to that of AK Amano commercial lipase. The purpose of this study was to obtain mutant fungi with higher transesterification activities than the wild type (KB). The mutation process was carried out using ultraviolet (UV) light, ethyl methane sulfonate (EMS), and N-methyl-N’-nitro-N-nitrosoguanidine (NMNG) on KB fungus. The mutations using UV light produced 11 isolates, of which isolate m4.1KB1 produced a higher transesterification activity (0.172 U·mg-1) compared to the wild type. Mutant m5.7KB, which was generated from mutant m4.1KB1 treated using EMS, had its transesterification activity decreased to only 0.051 U·mg-1. Mutant m6.0,3KB2, which was resulted through NMNG treatment, experienced an increase in transesterification activity which was 91.2% higher than that of KB.Keywords: ethyl methane sulfonate, lipase, mutant fungi, N-methyl-N’-nitro-N-nitrosoguanidine, ultraviolet ABSTRAKLipase dimanfaatkan salah satunya dalam produksi biodiesel, yaitu dalam reaksi transesterifikasi. Kernel B (KB) merupakan kapang yang diisolasi dari limbah inti dan biji kelapa sawit, yang menghasilkan lipase sebagai katalis dalam reaksi transesterifikasi. Namun aktivitas transesterifikasi yang dihasilkan oleh lipase dari KB lebih rendah dibandingkan dengan lipase komersial AK Amano. Tujuan penelitian ini adalah mendapatkan mutan kapang dengan aktivitas transesterifikasi yang lebih tinggi dibandingkan tipe liarnya (KB). Proses mutasi dilakukan dengan menggunakan sinar ultraviolet (UV), ethyl methane sulfonate (EMS), dan N-methyl-N’-nitro-N-nitrosoguanidine (NMNG) terhadap kapang KB. Mutasi KB dengan menggunakan sinar UV menghasilkan 11 isolat, dimana isolat dengan kode m4.1KB1 menghasilkan aktivitas transesterifikasi yang lebih tinggi dibandingkan tipe liar, yaitu 0,172 U·mg-1. Mutan m5.7KB, yang dihasilkan dari mutan m4.1KB1 dengan perlakuan EMS, mengalami penurunan aktivitas transesterifikasi hingga hanya sebesar 0,051 U·mg-1. Mutan m6.0,3KB2 hasil perlakuan NMNG mengalami peningkatan aktivitas transesterifikasi sebesar 91,2% lebih tinggi dari KB.Kata Kunci: ethyl methane sulfonate, kapang mutan, lipase, N-methyl-N’-nitro-N-nitrosoguanidine, ultraviolet


1983 ◽  
Vol 3 (5) ◽  
pp. 946-955 ◽  
Author(s):  
M M Crerar ◽  
R Leather ◽  
E David ◽  
M L Pearson

To assess the functional role of RNA polymerase II in the regulation of transcription during muscle differentiation, we isolated and characterized a large number of independent alpha-amanitin-resistant (AmaR) mutants of L6 rat myoblasts that express both wild-type and altered RNA polymerase II activities. We also examined their myogenic (Myo) phenotype by determining their ability to develop into mature myotubes, to express elevated levels of muscle creatine kinase, and to synthesize muscle-characteristic proteins as detected by two-dimensional polyacrylamide gel electrophoresis. We found a two- to threefold increase in the frequency of clones with a myogenic-defective phenotype in the AmaR (RNA polymerase II) mutants as compared to control ethyl methane sulfonate-induced, 6-thioguanine-resistant (hypoxanthine, guanine phosphoribosyl transferase) mutants or to unselected survivors also exposed to ethyl methane sulfonate. Subsequent analysis showed that about half of these myogenic-defective AmaR mutants had a conditional Myo(ama) phenotype; when cultured in the presence of amanitin, they exhibited a Myo- phenotype; in its absence they exhibited a Myo+ phenotype. This conditional Myo(ama) phenotype is presumably caused by the inactivation by amanitin of the wild-type amanitin-sensitive RNA polymerase II activity and the subsequent rise in the level of mutant amanitin-resistant RNA polymerase II activity. In these Myo(ama) mutants, the wild-type RNA polymerase II is normally dominant with respect to the Myo+ phenotype, whereas the mutant RNA polymerase II is recessive and results in a Myo- phenotype only when the wild-type enzyme is inactivated. These findings suggest that certain mutations in the amaR structural gene for the amanitin-binding subunit of RNA polymerase II can selectively impair the transcription of genes specific for myogenic differentiation but not those specific for myoblast proliferation.


1983 ◽  
Vol 3 (5) ◽  
pp. 946-955 ◽  
Author(s):  
M M Crerar ◽  
R Leather ◽  
E David ◽  
M L Pearson

To assess the functional role of RNA polymerase II in the regulation of transcription during muscle differentiation, we isolated and characterized a large number of independent alpha-amanitin-resistant (AmaR) mutants of L6 rat myoblasts that express both wild-type and altered RNA polymerase II activities. We also examined their myogenic (Myo) phenotype by determining their ability to develop into mature myotubes, to express elevated levels of muscle creatine kinase, and to synthesize muscle-characteristic proteins as detected by two-dimensional polyacrylamide gel electrophoresis. We found a two- to threefold increase in the frequency of clones with a myogenic-defective phenotype in the AmaR (RNA polymerase II) mutants as compared to control ethyl methane sulfonate-induced, 6-thioguanine-resistant (hypoxanthine, guanine phosphoribosyl transferase) mutants or to unselected survivors also exposed to ethyl methane sulfonate. Subsequent analysis showed that about half of these myogenic-defective AmaR mutants had a conditional Myo(ama) phenotype; when cultured in the presence of amanitin, they exhibited a Myo- phenotype; in its absence they exhibited a Myo+ phenotype. This conditional Myo(ama) phenotype is presumably caused by the inactivation by amanitin of the wild-type amanitin-sensitive RNA polymerase II activity and the subsequent rise in the level of mutant amanitin-resistant RNA polymerase II activity. In these Myo(ama) mutants, the wild-type RNA polymerase II is normally dominant with respect to the Myo+ phenotype, whereas the mutant RNA polymerase II is recessive and results in a Myo- phenotype only when the wild-type enzyme is inactivated. These findings suggest that certain mutations in the amaR structural gene for the amanitin-binding subunit of RNA polymerase II can selectively impair the transcription of genes specific for myogenic differentiation but not those specific for myoblast proliferation.


2018 ◽  
Vol 5 (1) ◽  
Author(s):  
Mahyudin Abdul Rachman

Enterobacter aerogenes AY-2 mutant is known for hydrogen gas producer which ws obtained from the sludge of methane fermentation and the yield is 1.5 fold higher than wildtype. Hydrogen gas production can be gain via NADH oxidation in anaerobic metabolic pathway by blocking organic acid production. Metabolic pathway can be changed by mutagenesis. Enterobacter aerogenes AY-2 mutated with ethyl methane sulfonate in logarithmic phase with consentration 10, 11, 12, 13, 14 and 15 μl/ml cell suspention during 120 minute. Mutation that result lowest survival ratio (0,01%) was 14 μl EMS/ml cell suspention is repeated with variation incubation time, 30, 60, 90 and 120 minute. 166 double mutant colony has been collected and choosen randomly. The choosen 43 colony was fermented in glycerol complex medium for determining ten double mutant with the highest H2 production. Double mutant AD-H43 is a highest H2 producer that increase 20% H2 production from AY-2 and has a decrease lactid acid production, 31% less from AY-2. Increasing H2 production in double mutant AD-H43 is caused by lactate dehydrogenase deffi cient.Keywords: Enterobacter aerogenes AY-2, ethyl methane sulfonate (EMS), H2 and methane sludge


2021 ◽  
Vol 171 ◽  
pp. 109640
Author(s):  
Vijayakumar Eswaramoorthy ◽  
Thangaraj Kandasamy ◽  
Kalaimagal Thiyagarajan ◽  
Chockalingam Vanniarajan ◽  
Souframanien Jegadeesan

Genetics ◽  
1973 ◽  
Vol 74 (3) ◽  
pp. 477-487
Author(s):  
Sumio Minamori ◽  
Kinue Sugimoto

ABSTRACT [Delta b], symbolized as [δb], is retained by Sb chromosome lines and transmitted through the females to their progeny. Transmission through the males is not directly demonstrable (Minamori 1969a). [delta r], symbolized as [δr], is retained by Sr chromosome lines and transmitted biparentally (Minamori 1971). The multiplication of delta is suppressed at low temperature. All descendant lines derived from Sb-carrying or Sr-carrying flies in which the presence of delta cannot be demonstrated gradually accumulate their specific delta factors over many generations (Minamori 1969b, 1972). The delta factors and the sensitive chromosomes are inseparably associated. This observation led to the assumption that delta may be a copy of a chromosomal gene or a certain agent integrated into the chromosome (Minamori 1972). This assumption was examined in the present study by experiments designed to induce delta-retaining sensitive chromosomes, and to map the gene(s) responsible for delta-retention and/or for sensitivity to the killing action of delta factor. One sensitive chromosome which retained [δb] (Sb chromosome) was obtained in the presence of [δb] out of 2492 insensitive chromosomes which retained no delta; in addition one Sb chromosome was obtained in the presence of [δr] out of 2131 insensitives. The latter finding suggests that Sb might be induced by a mutation caused by [δb] or [δr], but not by integration of either delta into the chromosome. Four Sb chromosomes and one sensitive chromosome which retained [δr] (Sr chromosome) were obtained out of 1970 insensitives when males carrying the chromosome were fed an alkylating mutagen, ethyl methane sulfonate (EMS). The location of delta-retaining genes was examined by crossing-over experiments employing eight Sb and five Sr chromosomes. The genes on these chromosomes were found to be located in the same region or near one another. The gene for [δb], symbolized as Dab, and the gene for [δr], symbolized as Dar, are assumed to be multiple alleles of a locus at 2-24.9. The sensitivity of the chromosomes was modified appreciably by recombination; hence, the genes controlling this trait are assumed to be a polygenic system. The findings obtained in this study lead to the hypothesis that delta may be produced by a chromosomal gene (Da) and transmitted extrachromosomally.


2021 ◽  
Vol 16 (7) ◽  
pp. 64-70
Author(s):  
Priya Chaudhary ◽  
Arun Kumar Sharma ◽  
Pracheta Janmeda

Enhancement in the production of enzyme by utilizing different strains of microbe is one of the main prospects in biotechnology. In the present work, ethyl methane sulfonate (EMF) was selected as the chemical mutagen for inducing mutagenesis in fungi. It is a cheap method to induce random mutation as compared to other methods of recombinant technologies. Strain improvement was done by incubating the fungal spore suspension at variable concentrations of EMS i.e. 4% (v/v) and 10% (v/v) for the time period of 60, 90, and 120 min respectively. The set of control was treated with distilled water only. The fungal colonies were found to be maximum in control plate as compared to the EMF exposed plates. The number of fungal colonies was reduced as we raised the exposure time of EMF. Specific activity and the lipase activity of wild strain and hyperproducer were evaluated under the submerged (SmF) and solid-state fermentation (SSF). The wild strain denoted the 3.2 U/ml/min of enzymatic activity under SmF and 15.87 U/g/min of activity under SSF. In contrast, the best enzymatic activity was represented by S2St1 at 10% of EMS after the time period of 60 min i.e. 11.7 U/ml/min under SmF and 99.35 U/g/min under SSF after the time period of 72 hrs. Statistical analysis by using one-way ANOVA determined that the value of F calculated was lower than the F tabulated. So, there was a significant relation between the EMS percentage and time of exposure among the mutated strains. In conclusion, this soil fungal strain can be utilized to produce lipase enzyme for numerous industrial applications.


2001 ◽  
Vol 43 (6) ◽  
Author(s):  
Carlos Alvarez-Moya ◽  
Anne Santerre-Lucas ◽  
Guillermo Zúñiga-González ◽  
Olivia Torres-Bugarín ◽  
Eduardo Padilla-Camberos ◽  
...  

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