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Upadhyaya C, Patel H, Patel I, Ahir P, Upadhyaya T. Development of Biological Coating from Novel Halophilic Exopolysaccharide Exerting Shelf-Life-Prolonging and Biocontrol Actions for Post-Harvest Applications. Molecules 2024; 29:695. [PMID: 38338439 PMCID: PMC10856335 DOI: 10.3390/molecules29030695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 01/22/2024] [Accepted: 01/31/2024] [Indexed: 02/12/2024] Open
Abstract
The literature presents the preserving effect of biological coatings developed from various microbial sources. However, the presented work exhibits its uniqueness in the utilization of halophilic exopolysaccharides as food coating material. Moreover, such extremophilic exopolysaccharides are more stable and economical production is possible. Consequently, the aim of the presented research was to develop a coating material from marine exopolysaccharide (EPS). The significant EPS producers having antagonistic attributes against selected phytopathogens were screened from different marine water and soil samples. TSIS01 isolate revealed the maximum antagonism well and EPS production was selected further and characterized as Bacillus tequilensis MS01 by 16S rRNA analysis. EPS production was optimized and deproteinized EPS was assessed for biophysical properties. High performance thin layer chromatography (HPTLC) analysis revealed that EPS was a heteropolymer of glucose, galactose, mannose, and glucuronic acid. Fourier transform infrared spectroscopy, X-ray diffraction, and UV-visible spectra validated the presence of determined sugars. It showed high stability at a wide range of temperatures, pH and incubation time, ≈1.63 × 106 Da molecular weight, intermediate solubility index (48.2 ± 3.12%), low water holding capacity (12.4 ± 1.93%), and pseudoplastic rheologic shear-thinning comparable to xanthan gum. It revealed antimicrobial potential against human pathogens and antioxidants as well as anti-inflammatory potential. The biocontrol assay of EPS against phytopathogens revealed the highest activity against Alternaria solani. The EPS-coated and control tomato fruits were treated with A. solani suspension to check the % disease incidence, which revealed a significant (p < 0.001) decline compared to uncoated controls. Moreover, it revealed shelf-life prolonging action on tomatoes comparable to xanthan gum and higher than chitosan. Consequently, the presented marine EPS was elucidated as a potent coating material to mitigate post-harvest losses.
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Affiliation(s)
- Chandni Upadhyaya
- School of Sciences, P. P. Savani University, Surat 394125, Gujarat, India
| | - Hiren Patel
- School of Sciences, P. P. Savani University, Surat 394125, Gujarat, India
- School of Agriculture, P. P. Savani University, Surat 394125, Gujarat, India
| | - Ishita Patel
- Shree P. M. Patel Institute of Integrated M. Sc. in Biotechnology, Sardar Patel University, Anand 388001, Gujarat, India
| | - Parth Ahir
- Shree P. M. Patel Institute of P. G. Studies in Research and Sciences, Sardar Patel University, Anand 388001, Gujarat, India
| | - Trushit Upadhyaya
- Chandubhai S. Patel Institute of Technology, Charotar University of Science & Technology, Changa, Anand 388421, Gujarat, India;
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Exopolysaccharide production from Alkalibacillus sp. w3: statistical optimization and biological activity. Biologia (Bratisl) 2022. [DOI: 10.1007/s11756-022-01233-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
AbstractMicrobial exopolysaccharides (EPS) provide a broad range of applications. Thus, there is an increasing interest in the production, characterization, and use of EPS derived from various microorganisms. Extremophile polysaccharides have unique properties and applications due to its unique structures. The importance of exopolysaccharides synthesized by a new bacterial strain, Alkalibacillus sp. w3, was highlighted in this study. Alkalibacillus sp. w3, a haloalkalitolerant firmicute that was recovered from a salt lake, was optimized for EPS production, and its biological activities were studied. Exopolysaccharide synthesis was observed in Horikoshi I broth medium. The optimal culture conditions for achieving the highest exopolysaccharide production were a 7-day incubation period, pH 10, and 250 g/L of NaCl. The most effective carbon and nitrogen sources for EPS production were glucose and a combination of yeast extract and peptone. Additionally, Plackett-statistical Burman’s design showed that all factors tested had a favorable impact, with glucose having the greatest significance on the production of EPS. The model’s best predictions for culture conditions resulted in a two-fold improvement in EPS production compared to the original yield before optimization. The recovered EPS contained 65.13% carbohydrates, 30.89% proteins, and 3.98% lipids. Moreover, EPS produced by Alkalibacillus sp. w3 demonstrated anticancer activity against hepatocellular carcinoma (HepG2) and human colon carcinoma (HCT-116) cell lines, with IC50 values as low as 11.8 and 15.5 µg/mL, respectively, besides antibacterial activity against various Gram-positive, Gram-negative bacteria, and yeast. Based on these results, EPS made by Alkalibacillus sp. w3 has many useful properties, which make it suitable for use in the medical field.
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Geng J, Sui Z, Dou W, Miao Y, Wang T, Wei X, Chen S, Zhang Z, Xiao J, Huang D. 16S rRNA Gene Sequencing Reveals Specific Gut Microbes Common to Medicinal Insects. Front Microbiol 2022; 13:892767. [PMID: 35651499 PMCID: PMC9149300 DOI: 10.3389/fmicb.2022.892767] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 04/27/2022] [Indexed: 11/24/2022] Open
Abstract
Insects have a long history of being used in medicine, with clear primary and secondary functions and less side effects, and the study and exploitation of medicinal insects have received increasing attention. Insects gut microbiota and their metabolites play an important role in protecting the hosts from other potentially harmful microbes, providing nutrients, promoting digestion and degradation, and regulating growth and metabolism of the hosts. However, there are still few studies linking the medicinal values of insects with their gut microbes. In this study, we focused on the specific gut microbiota common to medicinal insects, hoping to trace the potential connection between medicinal values and gut microbes of medicinal insects. Based on 16S rRNA gene sequencing data, we compared the gut microbiota of medicinal insects [Periplaneta americana, Protaetia (Liocola) brevitarsis (Lewis) and Musca domestica], in their medicinal stages, and non-medicinal insects (Hermetia illucens L., Tenebrio molitor, and Drosophila melanogaster), and found that the intestinal microbial richness of medicinal insects was higher, and there were significant differences in the microbial community structure between the two groups. We established a model using a random-forest method to preliminarily screen out several types of gut microbiota common to medicinal insects that may play medicinal values: Parabacteroides goldsteinii, Lactobacillus dextrinicus, Bifidobacterium longum subsp. infantis (B. infantis), and Vagococcus carniphilus. In particular, P. goldsteinii and B. infantis were most probably involved in the anti-inflammatory effects of medicinal insects. Our results revealed an association between medicinal insects and their gut microbes, providing new development directions and possibly potential tools for utilizing microbes to enhance the medicinal efficacy of medicinal insects.
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Affiliation(s)
- Jin Geng
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Zhuoxiao Sui
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Weihao Dou
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Yunheng Miao
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Tao Wang
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Xunfan Wei
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Sicong Chen
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Zongqi Zhang
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Jinhua Xiao
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
| | - Dawei Huang
- Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China
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Borkar SR, Bhosle SN. Partial characterization of viscous exopolymer produced by Alkalihalobacillus sp. strain SB-D (KJ372395) with emulsification and adhesive properties. Arch Microbiol 2021; 204:48. [DOI: 10.1007/s00203-021-02679-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 10/21/2021] [Accepted: 10/25/2021] [Indexed: 10/19/2022]
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Jaroszuk-Ściseł J, Nowak A, Komaniecka I, Choma A, Jarosz-Wilkołazka A, Osińska-Jaroszuk M, Tyśkiewicz R, Wiater A, Rogalski J. Differences in Production, Composition, and Antioxidant Activities of Exopolymeric Substances (EPS) Obtained from Cultures of Endophytic Fusarium culmorum Strains with Different Effects on Cereals. Molecules 2020; 25:E616. [PMID: 32019268 PMCID: PMC7037457 DOI: 10.3390/molecules25030616] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 01/24/2020] [Accepted: 01/28/2020] [Indexed: 11/16/2022] Open
Abstract
Exopolymeric substances (EPS) can determine plant-microorganism interactions and have great potential as bioactive compounds. The different amounts of EPS obtained from cultures of three endophytic Fusarium culmorum strains with different aggressiveness-growth promoting (PGPF), deleterious (DRMO), and pathogenic towards cereal plants-depended on growth conditions. The EPS concentrations (under optimized culture conditions) were the lowest (0.2 g/L) in the PGPF, about three times higher in the DRMO, and five times higher in the pathogen culture. The EPS of these strains differed in the content of proteins, phenolic components, total sugars, glycosidic linkages, and sugar composition (glucose, mannose, galactose, and smaller quantities of arabinose, galactosamine, and glucosamine). The pathogen EPS exhibited the highest total sugar and mannose concentration. FTIR analysis confirmed the β configuration of the sugars. The EPS differed in the number and weight of polysaccharidic subfractions. The EPS of PGPF and DRMO had two subfractions and the pathogen EPS exhibited a subfraction with the lowest weight (5 kDa). The three EPS preparations (ethanol-precipitated EP, crude C, and proteolysed P) had antioxidant activity (particularly high for the EP-EPS soluble in high concentrations). The EP-EPS of the PGPF strain had the highest antioxidant activity, most likely associated with the highest content of phenolic compounds in this EPS.
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Affiliation(s)
- Jolanta Jaroszuk-Ściseł
- Department of Industrial and Environmental Microbiology, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland; (R.T.); (A.W.)
| | - Artur Nowak
- Department of Industrial and Environmental Microbiology, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland; (R.T.); (A.W.)
| | - Iwona Komaniecka
- Department of Genetic and Microbiology, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland; (I.K.); (A.C.)
| | - Adam Choma
- Department of Genetic and Microbiology, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland; (I.K.); (A.C.)
| | - Anna Jarosz-Wilkołazka
- Department of Biochemistry and Biotechnology, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland; (A.J.-W.); (M.O.-J.); (J.R.)
| | - Monika Osińska-Jaroszuk
- Department of Biochemistry and Biotechnology, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland; (A.J.-W.); (M.O.-J.); (J.R.)
| | - Renata Tyśkiewicz
- Department of Industrial and Environmental Microbiology, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland; (R.T.); (A.W.)
- Military Institute of Hygiene and Epidemiology, Lubelska St. 2, 24-100 Puławy, Poland
| | - Adrian Wiater
- Department of Industrial and Environmental Microbiology, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland; (R.T.); (A.W.)
| | - Jerzy Rogalski
- Department of Biochemistry and Biotechnology, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland; (A.J.-W.); (M.O.-J.); (J.R.)
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Mamo G, Mattiasson B. Alkaliphiles: The Versatile Tools in Biotechnology. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2020; 172:1-51. [PMID: 32342125 DOI: 10.1007/10_2020_126] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The extreme environments within the biosphere are inhabited by organisms known as extremophiles. Lately, these organisms are attracting a great deal of interest from researchers and industrialists. The motive behind this attraction is mainly related to the desire for new and efficient products of biotechnological importance and human curiosity of understanding nature. Organisms living in common "human-friendly" environments have served humanity for a very long time, and this has led to exhaustion of the low-hanging "fruits," a phenomenon witnessed by the diminishing rate of new discoveries. For example, acquiring novel products such as drugs from the traditional sources has become difficult and expensive. Such challenges together with the basic research interest have brought the exploration of previously neglected or unknown groups of organisms. Extremophiles are among these groups which have been brought to focus and garnering a growing importance in biotechnology. In the last few decades, numerous extremophiles and their products have got their ways into industrial, agricultural, environmental, pharmaceutical, and other biotechnological applications.Alkaliphiles, organisms which thrive optimally at or above pH 9, are one of the most important classes of extremophiles. To flourish in their extreme habitats, alkaliphiles evolved impressive structural and functional adaptations. The high pH adaptation gave unique biocatalysts that are operationally stable at elevated pH and several other novel products with immense biotechnological application potential. Advances in the cultivation techniques, success in gene cloning and expression, metabolic engineering, metagenomics, and other related techniques are significantly contributing to expand the application horizon of these remarkable organisms of the 'bizarre' world. Studies have shown the enormous potential of alkaliphiles in numerous biotechnological applications. Although it seems just the beginning, some fantastic strides are already made in tapping this potential. This work tries to review some of the prominent applications of alkaliphiles by focusing such as on their enzymes, metabolites, exopolysaccharides, and biosurfactants. Moreover, the chapter strives to assesses the whole-cell applications of alkaliphiles including in biomining, food and feed supplementation, bioconstruction, microbial fuel cell, biofuel production, and bioremediation.
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Affiliation(s)
| | - Bo Mattiasson
- Department of Biotechnology, Lund University, Lund, Sweden
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Khalikova E, Somersalo S, Korpela T. Metabolites Produced by Alkaliphiles with Potential Biotechnological Applications. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2019; 172:157-193. [PMID: 31240347 DOI: 10.1007/10_2019_96] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Alkaliphiles are a diverse group of relatively less known microorganisms living in alkaline environments. To thrive in alkaline environments, alkaliphiles require special adaptations. This adaptation may have evolved metabolites which can be useful for biotechnological processes or other applications. In fact, certain metabolites are found unique to alkaliphiles or are effectively produced by alkaliphiles. This probably aroused the interest in metabolites of alkaliphiles. During recent years, many alkaliphilic microbes have been isolated, especially in countries having alkaline environments, like soda lakes. Even if the number of such isolated alkaliphiles is large, their metabolites have not yet been extensively analyzed and exploited. This is expected to come in the years ahead. So far, the focus of interests in metabolites from alkaliphiles falls into categories such as organic acids, ingredients for foodstuffs and cosmetics, antibiotics, and substances which modify properties of other materials used in industry. This chapter deals with biotechnologically important metabolites of alkaliphiles including compatible solutes, biosurfactants, siderophores, carotenoids, exopolysaccharides, and antimicrobial agents. It also covers the promising potential of alkaliphiles as sources of bioplastic raw materials. Moreover, an overview of the patent literature related to alkaliphiles is highlighted. Graphical Abstract.
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Affiliation(s)
- Elvira Khalikova
- Joint Biotechnology Laboratory, University of Turku, Turku, Finland
| | | | - Timo Korpela
- Department of Future Technologies, University of Turku, Turku, Finland.
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Chang H, Dai F, Duan B, Duan G, Zu F, Yang Z, Li H, Zhu Q, Zhang S, Xiang X. Isolation and characterization of Vagococcus carniphilus from diseased crucian carp. BIOTECHNOL BIOTEC EQ 2017. [DOI: 10.1080/13102818.2017.1413420] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Affiliation(s)
- Hua Chang
- Department of Veterinary Public Health, College of Veterinary Medicine, Yunnan Agricultural University, Kunming, P. R. China
| | - Feiyan Dai
- Department of Veterinary Public Health, College of Veterinary Medicine, Yunnan Agricultural University, Kunming, P. R. China
| | - Bofang Duan
- Animal Disease Prevention and Control Center of Yunnan Province, Kunming, P. R. China
| | - Gang Duan
- Department of Veterinary Public Health, College of Veterinary Medicine, Yunnan Agricultural University, Kunming, P. R. China
| | - Fei Zu
- Department of Veterinary Public Health, College of Veterinary Medicine, Yunnan Agricultural University, Kunming, P. R. China
| | - Zhiyuan Yang
- Department of Veterinary Public Health, College of Veterinary Medicine, Yunnan Agricultural University, Kunming, P. R. China
| | - Haoxing Li
- Department of Veterinary Public Health, College of Veterinary Medicine, Yunnan Agricultural University, Kunming, P. R. China
| | - Qi Zhu
- Department of Veterinary Public Health, College of Veterinary Medicine, Yunnan Agricultural University, Kunming, P. R. China
| | - Siqi Zhang
- Department of Veterinary Public Health, College of Veterinary Medicine, Yunnan Agricultural University, Kunming, P. R. China
| | - Xun Xiang
- Department of Veterinary Public Health, College of Veterinary Medicine, Yunnan Agricultural University, Kunming, P. R. China
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Exopolysaccharides of Halophilic Microorganisms: An Overview. Ind Biotechnol (New Rochelle N Y) 2016. [DOI: 10.1201/b19347-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Orlandelli RC, Vasconcelos AFD, Azevedo JL, Corradi da Silva MDL, Pamphile JA. Screening of endophytic sources of exopolysaccharides: Preliminary characterization of crude exopolysaccharide produced by submerged culture of Diaporthe sp. JF766998 under different cultivation time. BIOCHIMIE OPEN 2016; 2:33-40. [PMID: 29632836 PMCID: PMC5889487 DOI: 10.1016/j.biopen.2016.02.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 02/23/2016] [Indexed: 11/16/2022]
Abstract
Endophytic fungi have been described as producers of important bioactive compounds; however, they remain under-exploited as exopolysaccharides (EPS) sources. Therefore, this work reports on EPS production by submerged cultures of eight endophytes isolated from Piper hispidum Sw., belonging to genera Diaporthe, Marasmius, Phlebia, Phoma, Phyllosticta and Schizophyllum. After fermentation for 96 h, four endophytes secreted EPS: Diaporthe sp. JF767000, Diaporthe sp. JF766998, Diaporthe sp. JF767007 and Phoma herbarumJF766995. The EPS from Diaporthe sp. JF766998 differed statistically from the others, with a higher percentage of carbohydrate (91%) and lower amount of protein (8%). Subsequently, this fungus was grown under submerged culture for 72, 96 and 168 h (these EPS were designated EPSD1-72, EPSD1-96 and EPSD1-168) and the differences in production, monosaccharide composition and apparent molecular were compared. The EPS yields in mg/100 mL of culture medium were: 3.0 ± 0.4 (EPSD1-72), 15.4 ± 2.2 (EPSD1-96) and 14.8 ± 1.8 (EPSD1-168). The EPSD1-72 had high protein content (28.5%) and only 71% of carbohydrate; while EPSD1-96 and EPSD1-168 were composed mainly of carbohydrate (≈95 and 100%, respectively), with low protein content (≈5%) detected at 96 h. Galactose was the main monosaccharide component (30%) of EPSD1-168. Differently, EPSD1-96 was rich in glucose (51%), with molecular weight of 46.6 kDa. It is an important feature for future investigations, because glucan-rich EPS are reported as effective antitumor agents.
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Affiliation(s)
- Ravely Casarotti Orlandelli
- Universidade Estadual de Maringá, Departamento de Biotecnologia, Genética e Biologia Celular, CEP 87020-900, Maringá, Paraná, Brazil
| | - Ana Flora Dalberto Vasconcelos
- Universidade Estadual Paulista, Faculdade de Ciências e Tecnologia, Departamento de Química e Bioquímica, CEP 19060-900, Presidente Prudente, São Paulo, Brazil
| | - João Lúcio Azevedo
- Universidade de São Paulo, Escola Superior de Agricultura "Luiz de Queiroz", CEP 13418-900, Piracicaba, São Paulo, Brazil
| | - Maria de Lourdes Corradi da Silva
- Universidade Estadual Paulista, Faculdade de Ciências e Tecnologia, Departamento de Química e Bioquímica, CEP 19060-900, Presidente Prudente, São Paulo, Brazil
| | - João Alencar Pamphile
- Universidade Estadual de Maringá, Departamento de Biotecnologia, Genética e Biologia Celular, CEP 87020-900, Maringá, Paraná, Brazil
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Characterization and upregulation of bifunctional phosphoglucomutase/phosphomannomutase enzyme in an exobiopolymer overproducing strain of Acinetobacter haemolyticus. Microbiol Res 2015; 181:8-14. [PMID: 26640047 DOI: 10.1016/j.micres.2015.08.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2015] [Revised: 07/13/2015] [Accepted: 08/04/2015] [Indexed: 11/24/2022]
Abstract
Several members of the Acinetobacter spp. produce exobiopolymer (EBP) of considerable biotechnological interest. In a previous study, we reported phosphate removal capacity of EBP produced by Acinetobacter haemolyticus. Insertional mutagenesis was attempted to develop EBP-overproducing strains of A. haemolyticus and mutant MG606 was isolated. In order to understand the underlying mechanism of overproduction, the EBP overproducing mutant MG606 was analyzed and compared with the wild type counterpart for its key EBP synthetic enzymes. The EBP produced by MG606 mutant was 650 mg/L compared to 220 mg/L in its wild type counterpart. Significantly high (p<0.05) levels of phosphoglucomutase/phosphomannomutase (PGM/PMM) in MG606 mutant was noted, whereas activities of other enzymes responsible for EBP synthesis showed no significant change (p>0.05). The up-regulation of PGM/PMM expression in mutant was further confirmed by real time reverse transcriptase (RT)-PCR of PGM/PMM transcripts. The optimal conditions for PGM/PMM activity were found to be 35 °C and pH 7.5; PGM/PMM activity was inhibited by ions such as lithium, zinc, nickel. Further, incubation of cells with a PGM inhibitor (lithium) resulted in a concentration-dependent decrease in EBP production further confirming the role of PGM/PMM overexpression in enhanced EBP production by the mutant. Overall the results of our study indicate a key role of PGM/PMM in enhanced EBP production, as evident from enhanced enzyme activity, increased PGM/PMM transcripts and reduction in EBP synthesis by a PGM inhibitor. We envisage a potential exploitation of the insights so obtained to effectively engineer strains of Acinetobacter for overproducing phosphate binding EBP.
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The production of bioflocculants by Bacillus licheniformis using molasses and its application in the sugarcane industry. BIOTECHNOL BIOPROC E 2012. [DOI: 10.1007/s12257-012-0213-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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