1.Effectiveness of indigenous fluorescent pseudomonads in suppressing Rhizoctonia solani root rot disease and promoting plant growth in chilli seedlings
Ng Lee Chuen ; Rul-Hajar Muda ; Khairulmazmi Ahmad
Malaysian Journal of Microbiology 2021;17(2):200-211
Aims:
This study aimed to isolate and evaluate the indigenous fluorescent Pseudomonas spp. with bio-control potential
against Rhizoctonia solani and promoting growth in chilli seedlings.
Methodology:
A total of 120 fluorescent bacterial were isolated from the healthy chilli rhizosphere soil from the seven
major chilli cultivation localities in Terengganu, Malaysia. Only 115 Gram negative fluorescent isolates were further invitro screened for antagonistic activities against R. solani and plant growth-promoting properties. The 50 most effective
fluorescent Pseudomonads antagonist against R. solani with minimum percentage inhibition of radial growth (PIRG) of
65% were selected. Hierarchical cluster analysis was further conducted with two dendrograms derived from SPSS
Statistic 20 to facilitate the comparison between these 50 isolates for antagonistic and growth-promoting properties. A
total of 40 fluorescent isolates within the most potential cluster were further selected and identified using 16S rRNA
sequencing. Thirty four fluorescent isolates were identified as Pseudomonas spp. and six isolates as Burkholderia spp.
The top 13 ranked fluorescent Pseudomonas spp. from the scoring index were evaluated for seed germination and vigor
index in chilli seedlings. There was no significant difference in germination rate between fluorescent Pseudomonas
inoculated with control. However, vigor index of chilli seeds pre-inoculated with fluorescent P. putida (B5C1), P.
aeruginosa (B3C56) and P. putida (B5C7) were significantly increased with 4684.9, 4657.3 and 4401.0 over control (P ≤
0.05).
Conclusion, significance and impact of study
These selected fluorescent isolates: P. putida (B5C1), P. aeruginosa
(B3C56) and P. putida (B5C7) have the potential to be developed as biofungicide against R. solani and as growthpromoter in chilli production system.
Pseudomonas fluorescens
;
Rhizoctonia
;
Seedlings
2.Induction of Defense Related Enzymes and Pathogenesis Related Proteins in Pseudomonas fluorescens-Treated Chickpea in Response to Infection by Fusarium oxysporum f. sp. ciceri.
Ratul SAIKIA ; Rakesh KUMAR ; Tanuja SINGH ; Alok K SRIVASTAVA ; Dilip K ARORA ; Min Woong LEE
Mycobiology 2004;32(1):47-53
Pseudomonas fluorescens 1-94 induced systemic resistance in chickpea against Fusarium wilt of chickpea caused by Fusarium oxysporum f. sp. ciceri by the synthesis and accumulation of phenolic compounds, phenylalanine ammonia lyase(PAL) and pathogenesis related(PR) proteins(chitinase, beta-1,3-glucanase and peroxidase). Time-course accumulation of these enzymes in chickpea plants inoculated with P. fluorescens was significantly(LSD, P=0.05) higher than control. Maximum activities of PR-proteins were recorded at 3 days after inoculation in all induced plants; thereafter, the activity decreased progressively. Five PR peroxidases detected in induced chickpea plants. Molecular mass of these purified peroxidases was 20, 29, 43, 66 and 97 kDa. Purified peroxidases showed antifungal activity against plant pathogenic fungi.
Ammonia
;
Cicer*
;
Fungi
;
Fusarium*
;
Peroxidases
;
Phenol
;
Phenylalanine
;
Plants
;
Pseudomonas fluorescens
;
Pseudomonas*
3.Biological Control of Pythium Damping-off of Bush Okra Using Rhizosphere Strains of Pseudomonas fluorescens.
Hani M A ABDELZAHER ; M M IMAM ; M A SHOULKAMY ; Y M A GHERBAWY
Mycobiology 2004;32(3):139-147
A severe damping-off disease of bush okra caused by Pythium aphanidermatum, was diagnosed in plastic houses in Der Attia village, 15 km southwest of El-Minia city, Egypt, during the winter of 2001. Bush okra seedlings showed low emergence with bare patches inside the plastic houses. Seedlings that escaped pre-emergence damping-off showed poor growth, stunting and eventually collapsed. Examination of the infected tissues confirmed only Pythium aphanidermatum, showing its typical intercalary antheridia, and lobulate zoosporangia. P. aphanidermatum was shown to be pathogenic on bush okra under pot and field experiments. Bacteria making inhibition zones against the damping-off fungus P. aphanidermatum were selected. Agar discs from rhizosphere soil of bush okra containing colonies were transferred onto agar plate culture of P. aphanidermatum. After 2 days of incubation, colonies producing clear zones of non-Pythium growth were readily detected. The two bacteria with the largest inhibition zones were identified as Pseudomonas fluorescens. Bush okra emergence(%) in both pot and plastic houses experiments indicated that disease control could be obtained by applying P. fluorescens to the soil or coating the bacteria to the bush okra seeds before sowing. In the plastic houses, application of the bacteria onto Pythium-infested soil and sowing bush okra seeds dressed with bacteria gave 100% emergence. In addition, This was the first reported disease of bush okra by this oomycete in Egypt.
Abelmoschus*
;
Agar
;
Bacteria
;
Egypt
;
Fungi
;
Oomycetes
;
Plastics
;
Pseudomonas fluorescens*
;
Pseudomonas*
;
Pythium*
;
Rhizosphere*
;
Seedlings
;
Soil
;
United Nations
4.Effect of Iron Availability on Induction of Systemic Resistance to Fusarium Wilt of Chickpea by Pseudomonas spp..
Ratul SAIKIA ; Alok K SRIVASTAVA ; Kiran SINGH ; Dilip K ARORA ; Min Woong LEE
Mycobiology 2005;33(1):35-40
Selected isolates of Pseudomonas fluorescens (Pf4-92 and PfRsC5) and P. aeruginosa (PaRsG18 and PaRsG27) were examined for growth promotion and induced systemic resistance against Fusarium wilt of chickpea. Significant increase in plant height was observed in Pseudomonas treated plants. However, plant growth was inhibited when isolates of Pseudomonas were used in combination with Fusarium oxysporum f. sp. ciceri (FocRs1). It was also observed that the Pseudomonas spp. was colonized in root of chickpea and significantly suppressed the disease in greenhouse condition. Rock wool bioassay technique was used to study the effect of iron availability on the induction of systemic resistance to Fusarium wilt of chickpea mediated by the Pseudomonas spp. All the isolates of Pseudomonas spp. showed greater disease control in the induced systemic resistance (ISR) bioassay when iron availability in the nutrient solution was low. High performance liquid chromatography (HPLC) analysis indicated that all the bacterial isolates produced more salicylic acid (SA) at low iron (10microM EDDHA) than high iron availability (10microFe3+ EDDHA). Except PaRsG27, all the three isolates produced more pseudobactin at low iron than high iron availability.
Biological Assay
;
Chromatography, Liquid
;
Cicer*
;
Colon
;
Fusarium*
;
Iron*
;
Plants
;
Pseudomonas fluorescens
;
Pseudomonas*
;
Salicylic Acid
;
Wool
5.Enzymatic synthesis of monoglycerides in microaqueous media by using lipase from Pseudomonus fluorescens.
Yong-Mei XIA ; Ke-Chang ZHANG ; Gui-Yang SHI ; Xiao-Hui LI ; Yun FANG
Chinese Journal of Biotechnology 2002;18(1):84-88
Enzymatic synthesis of monoglycerides by glycerolysis of oil and fats in microaqueous solvent-free media was investigated by using lipase from pseudomonus fluorescens (PFL). Initial eutectic point(IEP) was substituted for melt point of oil and fats in Critical Temperature Theory. By investigating the glycerolysis under different IEP, it is showed that there is a relationship between composition of the oils and the yield of monoglycerides: Y = -0.0006 X3 + 0.0592 X2 - 0.8909 X + 26.753(13% < X < 76.5%), here X is the contents(W/W) of saturated fatty acid residue (C16 + C18) in the oils, Y is the yield of monoglycerides at 40 degrees C. The optimum isothermal reaction conditions for a system which IEP is 40 degrees C are: 40 degrees C, 3%-4.5% (W/W) water in glycerol, dosage of lipase is 500 u/g oil when the mole ratio of glycerol to oil is 2.5:1. The highest yield of monoglycerides is 81.4% in 48 h by means of programming temperature reaction.
Glycerides
;
metabolism
;
Glycerol
;
metabolism
;
Kinetics
;
Lipase
;
metabolism
;
Palm Oil
;
Plant Oils
;
metabolism
;
Pseudomonas fluorescens
;
enzymology
;
Substrate Specificity
;
Temperature
6.A Case of Pseudomonas fluorescens Infection after Dacryocystorhinostomy and Silicone Tube Intubation.
Jeong Yeop KANG ; Jae Ho YOO ; Jung Ju LEE ; Soo Young KIM ; Seung Uk LEE ; Sang Joon LEE
Journal of the Korean Ophthalmological Society 2013;54(4):655-658
PURPOSE: To report a case of Pseudomonas fluorescens infection following endoscopic dacryocystorhinostomy and silicone tube intubation in a healthy patient who was using steroid nasal spray. In addition, a literature review is conducted. CASE SUMMARY: A 72-year-old female patient came to our clinic with tearing and hyperemia in the right eye. Ten months prior, she had undergone endoscopic dacryocystorhinostomy and silicone tube intubation due to nasolacrimal duct obstruction in the right eye. Six months after the first operation, dacryocystorhinostomy revision with silicone tube exchange was performed due to obstruction of the nasal bony orifice. In addition, the patient was using a steroid nasal spray. On slit lamp examination, conjunctival injection, marked inflammation and punctal edema around the tube were observed. The silicone tube was removed and the tube cultured. Pseudomonas fluorescens was isolated from the tube contents. The patients was treated with topical 0.3% gatifloxacin 4 times a day, methylol cephalexin lysinate 1000 mg 3 times a day and the nasal spray was discontinued. Two weeks later, all symptoms were resolved after treatment with antibiotic treatment. CONCLUSIONS: A case of Pseudomonas fluorescens canaliculitis which occurred in healthy patient who was using steroid nasal spray is presented with a literature review. Pseudomonas fluorescens canaliculitis can be treated by using proper antibiotics.
Anti-Bacterial Agents
;
Cephalexin
;
Corneal Ulcer
;
Dacryocystitis
;
Dacryocystorhinostomy
;
Edema
;
Eye
;
Female
;
Fluoroquinolones
;
Humans
;
Hyperemia
;
Inflammation
;
Intubation
;
Nasolacrimal Duct
;
Porphyrins
;
Pseudomonas
;
Pseudomonas fluorescens
;
Silicones
;
Canaliculitis
7.Cloning, expression and characterization of a short-chain dehydrogenase from Pseudomonas fluorescens.
Qun XUE ; Xiangxian YING ; Chi YANG ; Zhao WANG
Chinese Journal of Biotechnology 2011;27(9):1317-1325
To explore the physiological role and biocatalytic properties of short-chain dehydrogenases from Pseudomonas fluorescens GIM1.49, we cloned the structural gene pfd and characterized its over-expressed product. The length of gene pfd was 684 bp encoding a short-chain dehydrogenase with 227 amino acid residues and calculated molecular mass of 24.2 kDa. The recombinant plasmid pET28b-pfd was constructed and functionally expressed in Escherichia coli BL21(DE3), resulting in the over-production of recombinant short-chain dehydrogenase PFD with a size of 28 kDa. The enzyme could oxidize alcohols including 4-chloro-3-hydroxbutanoate ester and reduce 4-chloro-acetoacetate ester using either NAD(H) or NADP(H) as coenzyme. The enzyme showed the highest activity against 4-chloro-3-hydroxbutanoate ester as substrate, with Km of 186.40 mmol/L and Vmax of 89.56 U/mg. When catalying the oxidative reaction, its optimal temperature was 12 degrees C and optimal pH was 10.5, in contrast to the values of 24 degrees C and pH 8.8 in the reductive reaction. The enzyme had high solvent tolerance and its activity was improved by the addition of Ca2+ (1 mmol/L) or EDTA (5 mmol/L). These results indicated that the enzyme from Pseudomonas fluorescens GIM1.49 was a novel short-chain dehydrogenase and might play a role in oxidative degradation of halogenated secondary alcohols.
Alcohols
;
metabolism
;
Bacterial Proteins
;
genetics
;
metabolism
;
Butyryl-CoA Dehydrogenase
;
genetics
;
metabolism
;
Cloning, Molecular
;
Escherichia coli
;
genetics
;
metabolism
;
Genetic Vectors
;
genetics
;
Oxidation-Reduction
;
Pseudomonas fluorescens
;
enzymology
;
genetics
;
Recombinant Proteins
;
genetics
;
metabolism
8.Anti-Bacterial Effect of Lactobacillus rhamnosus Cell-Free Supernatant Possessing Lysozyme Activity Against Pathogenic Bacteria
Jiyeon LEE ; Hyeji LIM ; Misook KIM
Journal of the Korean Dietetic Association 2018;24(4):330-343
Recently, there has been a growing demand for natural preservatives because of increased consumer interest in health. In this study, we produced Lactobacillus rhamnosus cell-free supernatant (LCFS) and evaluated and compared its antimicrobial activity with existing natural preservatives against pathogenic microorganisms and in chicken breast meat contaminated with Escherichia coli and Staphylococcus aureus. Lactobacillus rhamnosus cell-free supernatant possessed 30 units of lysozyme activity and contained 18,835 mg/L of lactic acid, 2,051 mg/L of citric acid and 5,060 mg/L of acetic acid. Additionally, LCFS inhibited the growth of fourteen pathogenic bacteria, S. aureus, Bacillus cereus, Listeria monocytogenes, Vibrio parahaemolyticus, Listeria innocua, S. epidermidis, L. ivanovii, E. coli, Pseudomonas aeruginosa, Shigella sonnei, Shi. flexneri, Proteus vulgaris, Pseudomonas fluorescens, and Klebsiella pneumoniae. The antibacterial activity of LCFS was stronger than that of egg white lysozyme (EWL), Durafresh (DF) and grapefruit seed extract (GSE). Additionally, LCFS maintained its antimicrobial activity after heat treatment at 50℃~95℃ and at pH values of 3~9. Moreover, LCFS inhibited the growth of E. coli and S. aureus in chicken breast meat. In conclusion, it is expected that LCFS, which contains both lysozyme and three organic acids, will be useful as a good natural preservative in the food industry.
Acetic Acid
;
Bacillus cereus
;
Bacteria
;
Breast
;
Chickens
;
Citric Acid
;
Citrus paradisi
;
Egg White
;
Escherichia coli
;
Food Industry
;
Hot Temperature
;
Hydrogen-Ion Concentration
;
Klebsiella pneumoniae
;
Lactic Acid
;
Lactobacillus rhamnosus
;
Lactobacillus
;
Listeria
;
Listeria monocytogenes
;
Meat
;
Muramidase
;
Proteus vulgaris
;
Pseudomonas aeruginosa
;
Pseudomonas fluorescens
;
Shigella sonnei
;
Staphylococcus aureus
;
Vibrio parahaemolyticus