Neutralization of Bacterial YoeBSpn Toxicity and Enhanced Plant Growth in Arabidopsis thaliana via Co-Expression of the Toxin-Antitoxin Genes.
Bacterial toxin-antitoxin (TA) systems have various cellular functions, including as part of the general stress response. The genome of the Gram-positive human pathogen Streptococcus pneumoniae harbors several putative TA systems, including yefM-yoeBSpn, which is one of four systems that had been demonstrated to be biologically functional. Overexpression of the yoeBSpn toxin gene resulted in cell stasis and eventually cell death in its native host, as well as in Escherichia coli. Our previous work showed that induced expression of a yoeBSpn toxin-Green Fluorescent Protein (GFP) fusion gene apparently triggered apoptosis and was lethal in the model plant, Arabidopsis thaliana. In this study, we investigated the effects of co-expression of the yefMSpn antitoxin and yoeBSpn toxin-GFP fusion in transgenic A. thaliana. When co-expressed in Arabidopsis, the YefMSpn antitoxin was found to neutralize the toxicity of YoeBSpn-GFP. Interestingly, the inducible expression of both yefMSpn antitoxin and yoeBSpn toxin-GFP fusion in transgenic hybrid Arabidopsis resulted in larger rosette leaves and taller plants with a higher number of inflorescence stems and increased silique production. To our knowledge, this is the first demonstration of a prokaryotic antitoxin neutralizing its cognate toxin in plant cells.
Centre for Research in Biotechnology for Agriculture (CEBAR) and Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia. afung87@gmail.com.
Fauziah
F
Abu Bakar
Biomedical Research Centre, Faculty of Medicine, Universiti Sultan Zainal Abidin, Medical Campus, 21300 Kuala Terengganu, Malaysia. chewchieng@gmail.com.
Chew Chieng
CC
Yeo
Centre for Research in Biotechnology for Agriculture (CEBAR) and Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia. jennihari@um.edu.my.
Jennifer Ann
JA
Harikrishna
D017209:Apoptosis / Q000235:genetics; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001427:Bacterial Toxins / Q000235:genetics* / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000032:analysis; D030821:Plants, Genetically Modified / Q000254:growth & development; D011993:Recombinant Fusion Proteins / Q000032:analysis / Q000235:genetics
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins
17-β-estradiol induction; Arabidopsis thaliana; YefM antitoxin; YoeB toxin; bacterial toxin-antitoxin; heterologous expression