Indole-3-acetic acid production by rhizobacteria Bacillus spp. to various abiotic stress factors

Indole-3-acetic acid (IAA) phytohormone plays an essential role in forming and initiating main, lateral, and adventitious roots in vegetative propagation. Plants are receiving IAA naturally from a diverse group of soil-plant associated rhizobacteria. However, IAA synthesis by rhizobacteria is influenced by abiotic growth conditions. Three indigenous Bacillus isolates were subject to in vitro assay for the effects of abiotic factors (temperature, salinity and pH) on growth and IAA production. All isolates grew well between 25 - 40°C, and only B. megaterium UPMLH3 was capable of synthesising IAA (21.18 µg/ml) at 40°C. All three bacterial growth under saline stress were slightly dropped over control (0% NaCl), but still producing IAA up to 1% NaCl condition. B. cereus UPMLH24 revealed high resistance to salinity up to 5% NaCl. The optimum growth of all three Bacillus spp. was at pH 7. B. cereus UPMLH1 and UPMLH24 discovered higher IAA production in slightly alkaline conditions (pH 8). Each rhizobacterium shows different physiology trait against each abiotic factor. However, the multiple tolerance ability of PGPR against abiotic factors is an indication that its ability to survive under harsh soil and plant environments while delivering benefits to the plant. Thus, B. cereus UPMLH1, B. megaterium UPMLH3 and B. cereus UPMLH24 might serve as potential biofertiliser, enhancing the growth performance of test plants at various environmental conditions.

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Volatile 1-octanol of tea (Camellia sinensis L.) fuels cell division and indole-3-acetic acid production in phylloplane isolate Pseudomonas sp. NEEL19

Scientific Reports ◽

10.1038/s41598-021-82442-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Poovarasan Neelakandan ◽

Chiu-Chung Young ◽

Asif Hameed ◽

Yu-Ning Wang ◽

Kui-Nuo Chen ◽

...

Keyword(s):

Acetic Acid ◽

Cell Division ◽

Petri Dish ◽

Gas Chromatography Mass Spectrometry ◽

Dependent Manner ◽

Tea Leaves ◽

Acetic Acid Production ◽

Iaa Production ◽

Solvent Tolerant ◽

Indole 3 Acetic Acid

AbstractTea leaves possess numerous volatile organic compounds (VOC) that contribute to tea’s characteristic aroma. Some components of tea VOC were known to exhibit antimicrobial activity; however, their impact on bacteria remains elusive. Here, we showed that the VOC of fresh aqueous tea leaf extract, recovered through hydrodistillation, promoted cell division and tryptophan-dependent indole-3-acetic acid (IAA) production in Pseudomonas sp. NEEL19, a solvent-tolerant isolate of the tea phylloplane. 1-octanol was identified as one of the responsible volatiles stimulating cell division, metabolic change, swimming motility, putative pili/nanowire formation and IAA production, through gas chromatography-mass spectrometry, microscopy and partition petri dish culture analyses. The bacterial metabolic responses including IAA production increased under 1-octanol vapor in a dose-dependent manner, whereas direct-contact in liquid culture failed to elicit such response. Thus, volatile 1-octanol emitting from tea leaves is a potential modulator of cell division, colonization and phytohormone production in NEEL19, possibly influencing the tea aroma.

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Tryptophan Regulates Thaxtomin A and Indole-3-Acetic Acid Production in Streptomyces scabiei and Modifies Its Interactions with Radish Seedlings

Phytopathology ◽

10.1094/phyto-03-11-0064 ◽

2011 ◽

Vol 101 (9) ◽

pp. 1045-1051 ◽

Cited By ~ 14

Author(s):

Geneviève S. Legault ◽

Sylvain Lerat ◽

Philippe Nicolas ◽

Carole Beaulieu

Keyword(s):

Acetic Acid ◽

Biosynthetic Genes ◽

Acetic Acid Production ◽

Thaxtomin A ◽

Iaa Production ◽

Streptomyces Scabiei ◽

Radish Seedlings ◽

Indole 3 Acetic Acid

The virulence of Streptomyces scabiei, the causal agent of common scab, depends mainly on the production of the toxin thaxtomin A. S. scabiei also produces indole-3-acetic acid (IAA) but the role of this hormone in the interaction between pathogenic streptomycetes and plants has not yet been elucidated. Tryptophan is a biosynthetic precursor of both IAA and thaxtomin A. In this study, the effect of tryptophan on thaxtomin A and IAA production as well as its effect on the transcription of the corresponding biosynthetic genes in S. scabiei has been analyzed. In vitro IAA production depended on the availability of tryptophan. However, addition of this amino acid to the culture medium inhibited the biosynthesis of thaxtomin A. Expression of thaxtomin A biosynthetic genes nos and txtA were strongly repressed in the presence of tryptophan; however, modulation of the expression was not observed for the IAA biosynthetic genes iaaM and iaaH. The effects of an exogenous tryptophan supply on S. scabiei virulence were assessed on radish seedlings. Addition of tryptophan reduced symptoms on inoculated radish roots compared with seedlings grown in the absence of the bacterium, by way of inhibition of thaxtomin A production and increase of IAA biosynthesis.

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Optimization of fermentation conditions through response surface methodology for Indole-3-acetic acid production by Marine Sponge Callyspongia diffusa associated Pseudomonas fluorescens BCPBMS-1

10.21203/rs.3.rs-53562/v1 ◽

2020 ◽

Author(s):

Vasanthabharathi Venkataraman ◽

LakshmiNarayanan Ramasamy ◽

Jayalakshmi Singaram

Keyword(s):

Response Surface Methodology ◽

Acetic Acid ◽

Response Surface ◽

Marine Sponge ◽

Soya Bean ◽

Gulf Of Mannar ◽

Acetic Acid Production ◽

Iaa Production ◽

Callyspongia Diffusa ◽

Indole 3 Acetic Acid

Abstract In the Present study we focused on the production and statistical optimization of media components for Indole-3 acetic acid (IAA) production from P.fluorescens BCPBMS-1, it was isolated from Marine sponge Callyspongia diffusa . This sponge was collected from Gulf of Mannar, Southeast coast of India. We optimized the low-cost agricultural residue based medium for IAA production. In our study Soya bean husk used as a substrate for Indole-3-acetic acid (IAA) production. Fermentation variables were selected based on the Plackett-Burman design and were optimized by response surface methodology. The maximum IAA concentration 1.7474 µg/ml was predicted in medium containing 3.1064% Soya bean husk, Yeast extract 0.8323%, Salinity 9.0765 ppt, pH 6.3108 temperature 27.5524℃, incubation time 64.7475hrs. These predicted values were also verified through experiments as a result we got 1.74 µg/ml. The excellent correlation observed between predicted and measured values of this statistical model hence, this method may recommend for the industrial purpose.

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Characterization of the indole-3-acetic acid (IAA) biosynthetic pathway in an epiphytic strain of Erwinia herbicola and IAA production in vitro

Canadian Journal of Microbiology ◽

10.1139/m96-079 ◽

1996 ◽

Vol 42 (6) ◽

pp. 586-592 ◽

Cited By ~ 35

Author(s):

M. Brandi ◽

E. M. Clark ◽

S. E. Lindow

Keyword(s):

Acetic Acid ◽

Pseudomonas Syringae ◽

Pyruvic Acid ◽

Enzyme Assays ◽

Erwinia Herbicola ◽

Iaa Production ◽

Acid Pathway ◽

Culture Supernatants ◽

Indole 3 Acetic Acid

An epiphytic strain of Erwinia herbicola (strain 299R) synthesized indole-3-acetic acid (IAA) from indole-3-pyruvic acid and indole-3-acetaldehyde, but not from indole-3-acetamide and other intermediates of various IAA biosynthetic pathways in enzyme assays. TLC, HPLC, and GC–MS analyses revealed the presence of indole-3-pyruvic acid, indole-3-ethanol, and IAA in culture supernatants of strain 299R. Indole-3-acetaldehyde was detected in enzyme assays. Furthermore, strain 299R genomic DNA shared no homology with the iaaM and iaaH genes from Pseudomonas syringae pv. savastanoi, even in Southern hybridizations performed under low-stringency conditions. These observations strongly suggest that unlike gall-forming bacteria which can synthesize IAA by indole-3-acetamide, the indole-3-pyruvic acid pathway is the primary route for IAA biosynthesis in this plant-associated strain. IAA synthesis in tryptophan-supplemented cultures of strain 299R was over 10-fold higher under nitrogen-limiting conditions, indicating a possible role for IAA production by bacterial epiphytes in the acquisition of nutrients during growth in their natural habitat.Key words: indole-3-acetic acid, Erwinia, tryptophan, indole-3-pyruvic acid, nitrogen.

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