A rapid and efficient method for in vitro shoot organogenesis and production of transgenic Bacopa monnieri L. mediated by Agrobacterium tumefaciens

2012 ◽  
Vol 48 (2) ◽  
pp. 153-159 ◽  
Author(s):  
Aileni Mahender ◽  
Bulle Mallesham ◽  
Kota Srinivas ◽  
Gadidasu Kranthi Kumar ◽  
Kokkirala Venugopal Rao ◽  
...  
Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 660
Author(s):  
Nataliya V. Varlamova ◽  
Yuliya I. Dolgikh ◽  
Andrey O. Blinkov ◽  
Ekaterina N. Baranova ◽  
Marat R. Khaliluev

A β-lactams that act by inhibiting the bacterial cell wall biosynthesis are one of the most common classes of antibiotics applied to suppress the growth of latent bacterial infection associated with the plant tissue culture, as well as in the Agrobacterium-mediated transformation techniques. Plant sensitivity to antibiotics usually is species-, genotype-, or even tissue-specific and mainly depends on concentrations, growth conditions, and culture system. In the presented article, we estimated a comparative effect of four β-lactam antibiotics (Claforan®, timentin, amoxicillin, and Amoxiclav®) at different concentrations in an agar-solidified Murashige and Skoog (MS) culture medium supplemented with 5 mg L−1 6-benzylaminopurine (6-BA) and 0.1 mg L−1 indole-3-acetic acid (IAA) on in vitro callus induction and shoot organogenesis from hypocotyl and cotyledon explants of two tomato cultivars (Rekordsmen, Moryana). The role of clavulanic acid in combination with amoxicillin (Amoxiclav®) in the shoot organogenesis frequency and number of shoots per explant has been demonstrated. Additionally, the growth inhibition of Agrobacterium tumefaciens AGL0 strain according to agar disk-diffusion assay was studied. As a result, both stimulatory (timentin, amoxicillin, and Amoxiclav®) and inhibitory (Claforan®) effects of β-lactam antibiotics on in vitro morphogenetic responses of tomato were noted. It was found that clavulanic acid, which is part of the commercial antibiotic Amoxiclav®, significantly increased the shoot regeneration frequency from cotyledon and hypocotyl explants of Rekordsmen tomato cultivar. Possible reasons for the stimulating effect of clavulanic acid on the induction of shoot organogenesis are discussed. According to agar disk-diffusion assay, the maximum diameter of growth inhibition zones (43.9 mm) was identified using 200 mg L−1 timentin. The in vitro antibacterial activity of tested β-lactam antibiotics was arranged in the following order: timentin > Claforan® > amoxicillin ≥ Amoxiclav®. Thus, to suppress the growth of internal and latent bacterial infection of tomato plant tissue culture, as well as for transformation of Moryana and Rekordsmen cultivars by A. tumefaciens strain AGL0, we recommend adding of 100–200 mg L−1 timentin or 400–800 mg L−1 Amoxiclav® to the shoot induction medium.


2019 ◽  
Author(s):  
Erdal Can Alkoclar

BACKGROUND A Formulation consisting of 2 Dioscin and 2 Glucopyranoside Derivatives with Simultaneous GHRH Stimulative and T3 mRNA Expression Enhancimg Features. OBJECTIVE Anti Aging METHODS GH/T3 Optimization RESULTS Approved in Vitro CONCLUSIONS Endogenous GH and T3 Optimization is the an efficient method for combating age related Senility and Fatigue Symptoms


2021 ◽  
Vol 9 (5) ◽  
pp. 1107
Author(s):  
Wonho Choi ◽  
Yoshihiro Yamaguchi ◽  
Ji-Young Park ◽  
Sang-Hyun Park ◽  
Hyeok-Won Lee ◽  
...  

Agrobacterium tumefaciens is a pathogen of various plants which transfers its own DNA (T-DNA) to the host plants. It is used for producing genetically modified plants with this ability. To control T-DNA transfer to the right place, toxin-antitoxin (TA) systems of A. tumefaciens were used to control the target site of transfer without any unintentional targeting. Here, we describe a toxin-antitoxin system, Atu0939 (mazE-at) and Atu0940 (mazF-at), in the chromosome of Agrobacterium tumefaciens. The toxin in the TA system has 33.3% identity and 45.5% similarity with MazF in Escherichia coli. The expression of MazF-at caused cell growth inhibition, while cells with MazF-at co-expressed with MazE-at grew normally. In vivo and in vitro assays revealed that MazF-at inhibited protein synthesis by decreasing the cellular mRNA stability. Moreover, the catalytic residue of MazF-at was determined to be the 24th glutamic acid using site-directed mutagenesis. From the results, we concluded that MazF-at is a type II toxin-antitoxin system and a ribosome-independent endoribonuclease. Here, we characterized a TA system in A. tumefaciens whose understanding might help to find its physiological function and to develop further applications.


Plants ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 1261
Author(s):  
Robin Lardon ◽  
Danny Geelen

Plant regeneration is essential for survival upon wounding and is, hence, considered to be a strong natural selective trait. The capacity of plant tissues to regenerate in vitro, however, varies substantially between and within species and depends on the applied incubation conditions. Insight into the genetic factors underlying this variation may help to improve numerous biotechnological applications that exploit in vitro regeneration. Here, we review the state of the art on the molecular framework of de novo shoot organogenesis from root explants in Arabidopsis, which is a complex process controlled by multiple quantitative trait loci of various effect sizes. Two types of factors are distinguished that contribute to natural regenerative variation: master regulators that are conserved in all experimental systems (e.g., WUSCHEL and related homeobox genes) and conditional regulators whose relative role depends on the explant and the incubation settings. We further elaborate on epigenetic variation and protocol variables that likely contribute to differential explant responsivity within species and conclude that in vitro shoot organogenesis occurs at the intersection between (epi) genetics, endogenous hormone levels, and environmental influences.


2009 ◽  
Vol 191 (7) ◽  
pp. 2033-2041 ◽  
Author(s):  
Meriyem Aktas ◽  
Franz Narberhaus

ABSTRACT Agrobacterium tumefaciens requires phosphatidylcholine (PC) in its membranes for plant infection. The phospholipid N-methyltransferase PmtA catalyzes all three transmethylation reactions of phosphatidylethanolamine (PE) to PC via the intermediates monomethylphosphatidylethanolamine (MMPE) and dimethylphosphatidylethanolamine (DMPE). The enzyme uses S-adenosylmethionine (SAM) as the methyl donor, converting it to S-adenosylhomocysteine (SAH). Little is known about the activity of bacterial Pmt enzymes, since PC biosynthesis in prokaryotes is rare. In this article, we present the purification and in vitro characterization of A. tumefaciens PmtA, which is a monomeric protein. It binds to PE, the intermediates MMPE and DMPE, the end product PC, and phosphatidylglycerol (PG) and phosphatidylinositol. Binding of the phospholipid substrates precedes binding of SAM. We used a coupled in vitro assay system to demonstrate the enzymatic activity of PmtA and to show that PmtA is inhibited by the end products PC and SAH and the antibiotic sinefungin. The presence of PG stimulates PmtA activity. Our study provides insights into the catalysis and control of a bacterial phospholipid N-methyltransferase.


2006 ◽  
Vol 41 (3) ◽  
pp. 385-391 ◽  
Author(s):  
Daniela Anhel de Paula Cidade ◽  
Renata de Oliveira Garcia ◽  
Aline Castellar Duarte ◽  
Gilberto Sachetto-Martins ◽  
Elisabeth Mansur

O objetivo deste trabalho foi estabelecer sistemas de multiplicação de plantas de cana-de-açúcar in vitro e avaliar sua utilização, como material inicial, para a indução de regeneração a partir de ápices caulinares. Três métodos de cultivo foram avaliados: cultura em meio semi-sólido, cultura líquida estacionária e cultura líquida sob agitação. A taxa de multiplicação mais elevada foi alcançada por meio da cultura líquida sob agitação. Ápices caulinares, excisados dessas plantas, apresentaram taxas de regeneração in vitro compatíveis com sua utilização em protocolos de transformação. Calos resistentes a PPT e GUS-positivos foram obtidos de explantes da variedade Chunnee com inoculação de Agrobacterium tumefaciens C58C1 (pMP90) (pDUBarA9). O protocolo estabelecido a partir de cultivo in vitro pode ser utilizado para a produção de plantas transgênicas de cana-de-açúcar, visando à realização de estudos de regulação da expressão gênica, assim como à introdução de características de interesse agronômico.


Sign in / Sign up

Export Citation Format

Share Document