Clavulanic acid (CA) is a commercially important broad-spectrum β-lactamase inhibitor that was pr... more Clavulanic acid (CA) is a commercially important broad-spectrum β-lactamase inhibitor that was produced by Streptomyces clavuligerus. The first step in the biosynthesis of CA is the condensation of two primary metabolites, D-glyceraldehyde 3-phosphate and Larginine, to give N2-(2-carboxyethyl)-L- arginine (CEA). Analysis of CEA in the fermentation broth of Streptomyces clavuligerus RFL35 is investigated by using benzoin as a fluorogenic reagent. The method is based on reverse-phase high performance liquid chromatography (HPLC) following pre-column derivatization with benzoin and fluorescence detection. CEA appears in chromatogram in a retention time of 4.7 min. This finding may help to enhance CA production by optimizing the fermentation medium and genetic manipulation of Streptomyces clavuligerus. It may also facilitate the structural and mechanistic studies on N2-(2-carboxyethyl)-L-arginine synthase that catalyzes an unusual N-C bond forming reaction.
Article Information Monascus purpureus is a fungus that had been cultured on the rice in eastern ... more Article Information Monascus purpureus is a fungus that had been cultured on the rice in eastern Asian countries since thousands years ago and used as a food for long years. The fungus produces very valuable metabolites with polyketide structure. The most important metabolite is Monacolin K, lovastatin or competitive inhibitor of 3-Hydroxy-3-Methylglutaryl-Coenzyme A reductase (an affective enzyme in cholesterol synthesis). This metabolite has various properties including reducing blood cholesterol, preventing infection, and treatment of progressive renal disease, a variety of tumors, vascular diseases and bone fractures. In this study, Monascus purpureus PTCC5303 has been used for lovastatin production in liquid fermentation. The nutritional concentrations that were significant in biomass and lovastatin production including maltose and MgSO 4 were optimized by Response Surface Methodology in a mili-bioreactor. The optimum concentration of maltose and MgSO 4 was obtained as 10 gl-1 ...
Metal ions are the main impurities of water and media ingredients used in fermentation processes.... more Metal ions are the main impurities of water and media ingredients used in fermentation processes. In this research, the effect of Ca+2, Co+2, Cu+2, Fe+2, Mg+2, Mn+2 and Zn+2 as chloride and sulfate salts was studied on the clavulanic acid production and Streptomyces clavuligerus growth. All chloride salts had negative effect on clavulanic acid production and no clavulanic acid was produced in the media containing more than 1.5 mM ZnCl2 and 18 mM FeCl2. CuCl2 and CaCl2 increased biomass production, while the other chloride salts decreased it. Concentration of clavulanic acid in the 0.2 mM MnSO4 containing medium was 1.21 times more than that of control. There was no significant difference in antibiotic concentration in the medium containing 0.41 mM MgSO4 and control. Other sulfate salts decreased antibiotic production. MgSO4, CuSO4 and FeSO4 increased the biomass, while other sulfate salts decreased it. Minimum and maximum specific consumption rate of glycerol were seen in the medium...
Behnoosh Sadat Khalili 1 , Javad Hamedi 2, 3* , Setareh Haghighat 1. Department of Microbiology, ... more Behnoosh Sadat Khalili 1 , Javad Hamedi 2, 3* , Setareh Haghighat 1. Department of Microbiology, Faculty of Advanced Sciences and Technologies, Pharmaceutical Sciences Branch, Islamic Azad University, Tehran, Iran. 2. Department of Microbial Biotechnology, School of Biology and Center of Excellence in Phylogeny of Living Organisms, College of Science, University of Tehran, Tehran, Iran. 3. Microbial Technology and Products Research Center, University of Tehran, Tehran, Iran.
Monascus purpureus is a fungus that had been cultured on the rice in eastern Asian countries sinc... more Monascus purpureus is a fungus that had been cultured on the rice in eastern Asian countries since thousands years ago and used as a food for long years. The fungus produces very valuable metabolites with polyketide structure. The most important metabolite is Monacolin K, lovastatin or competitive inhibitor of 3-Hydroxy-3-Methylglutaryl-Coenzyme A reductase (an affective enzyme in cholesterol synthesis). This metabolite has various properties including reducing blood cholesterol, preventing infection, and treatment of progressive renal disease, a variety of tumors, vascular diseases and bone fractures. In this study, Monascus purpureus PTCC5303 has been used for lovastatin production in liquid fermentation. The nutritional concentrations that were significant in biomass and lovastatin production including maltose and MgSO4 were optimized by Response Surface Methodology in a mili-bioreactor. The optimum concentration of maltose and MgSO4 was obtained as 10 g l-1 and 0.78 g l-1, respe...
Lipases are the biocatalysts with outstanding prospects in industry and medicine. They have prove... more Lipases are the biocatalysts with outstanding prospects in industry and medicine. They have proven to be useful in various hydrolytic and synthetic reactions. However, there are some limitations for impure lipases that may restrict their widely uses in industrial applications. Purification is sometimes vital for the characterization of the function, structure, and interactions of lipases. The lipase immobilization is also an efficient strategy for increasing the enzyme activity and stability, and getting a simpler recovery. Lipases are naturally produced together with many other proteins that they may occupy some surface of immobilization solid support and decrease the final activity. The coupling of immobilization and purification of lipase will overcome the mentioned problems and obtain the maximum purification yields. The present mini-review will discuss the use of the techniques that permit to join immobilization and purification of lipases in a single step, including control of...
IJMM 1394; 9(4): 63-72 Background and Aim: Environmental pollution by petroleum compounds have tu... more IJMM 1394; 9(4): 63-72 Background and Aim: Environmental pollution by petroleum compounds have turned into one of the global concerns. The aim of the present research was evaluation of the indigenous fungal strains of Iran to remove crude oil pollutants. Materials and Methods: First, the contaminated soil samples were collected. The samples were enriched in minimal salts medium (MSM) medium with 1% crude oil and chloramphenicol for 3 weeks and the isolates were purified. The crude oil degradation was measured by total petroleum hydrocarbon (TPH) assay method at 420 nm. In order to confirm the amount of oil degradation by selected isolate, the residual hydrocarbon content was evaluated by FTIR. Laccase activity in the presence of 1% crude oil was measured. Finally, the selected isolate was identified using morphological and molecular methods.
Production of extracellular amylase was demonstrated under conditions of high salinity in aerobic... more Production of extracellular amylase was demonstrated under conditions of high salinity in aerobically cultivated culture of a newly isolated moderately halophilic Gram-positive coccus, designated strain F in basal medium containing peptone from meat, yeast extract, NaCl (7% w/v) and starch. Biochemical and physiological characterization along with 16S rRNA sequence analysis placed F in the genus Nesterenkonia. The enzyme production was synchronized bacterial growth and reached a maximum level during the early-stationary phase in the basal medium. Maximum yield production was observed when the soluble starch, yeast extract and NaCl (1%, 0.75% and 10% w/v, respectively) were used in the fermentation medium with pH 8.0, inoculated with 7% (v/v) pre-culture medium and incubated in 30°C for 72 h with aeration of 250 rpm (299.25 U/ml). The potential of different carbohydrates in amylase production was in the order: starch> maltose>dextrin>fructose>lactose=glucose>sodium ace...
Exopolymers (EPS) are high-molecular-weight polymers secreted by some micro-organisms and have se... more Exopolymers (EPS) are high-molecular-weight polymers secreted by some micro-organisms and have several applications in food, pharmaceutical, packaging and agricultural industries, as well as medicine. Actinobacteria are valuable bacteria in biotechnology and many commercial drugs such as antibiotics, antioxidants and immune-suppressant agents are derived from Actinobacteria. Recently, their other capabilities such as exopolymer production have been taken into consideration. Due to the high potential of actinobacteria in producing various compounds and increased prevalence of infections by antibiotic-resistant pathogens, the aim of the present study was to evaluate the potential of isolated Actinobacteria from various locations of Iran to produce EPS with antimicrobial activity. Appropriate dilutions of the samples were, therefore, cultured in ISP2 medium after treatment. The isolates were primarily identified by morphological tests. Then, their ability to produce EPS was investigate...
Background and Objectives: Streptomyces tendae is one of the most prolific actinobacteria with a ... more Background and Objectives: Streptomyces tendae is one of the most prolific actinobacteria with a wide range of biotechnological applications. Genomic data can help in better understanding and exploration of important microorganisms, however, there is a few genomic information available for this species. Materials and Methods: Molecular identification, pH and salt tolerance of an actinobacterium, designated Streptomyces tendae UTMC 3329, isolated from a tea field soil were done. Also, genomic DNA was extracted and sequenced using Illumina platform with MPS (massively parallel sequencing) Illumina technology. Gene annotation and bioinformatic analysis were done using appropriate software and servers. Results: The draft genome is ~8.7 megabase pairs, containing 7557 predicted coding sequences. The strain was able to grow at pH 5-12 and 0-10% NaCl. The maximum growth rate of the bacterium was obtained at pH 7. The gene clusters involved in central carbon metabolism, phosphate regulation...
Transcription is of the most crucial steps of gene expression in bacteria, whose regulation guara... more Transcription is of the most crucial steps of gene expression in bacteria, whose regulation guarantees the bacteria’s ability to adapt to varying environmental conditions. Discovering the molecular basis and genomic principles of the transcriptional regulation is thus one of the most important tasks in cellular and molecular biology. Here, a comprehensive phylogenetic footprinting framework was implemented to predict maximal regulons of Lactococcus lactis subsp. lactis IO-1, a lactic acid bacterium known for its high potentials in nisin Z production as well as efficient xylose consumption which have made it a promising biotechnological strain. A total set of 321 regulons covering more than 90% of all the bacterium’s operons have been elucidated and validated according to available data. Multiple novel biologically-relevant members were introduced amongst which arsC, mtlA and mtl operon for BusR, MtlR and XylR regulons can be named, respectively. Moreover, the effect of riboflavin on...
Clavulanic acid (CA) is a commercially important broad-spectrum β-lactamase inhibitor that was pr... more Clavulanic acid (CA) is a commercially important broad-spectrum β-lactamase inhibitor that was produced by Streptomyces clavuligerus. The first step in the biosynthesis of CA is the condensation of two primary metabolites, D-glyceraldehyde 3-phosphate and Larginine, to give N2-(2-carboxyethyl)-L- arginine (CEA). Analysis of CEA in the fermentation broth of Streptomyces clavuligerus RFL35 is investigated by using benzoin as a fluorogenic reagent. The method is based on reverse-phase high performance liquid chromatography (HPLC) following pre-column derivatization with benzoin and fluorescence detection. CEA appears in chromatogram in a retention time of 4.7 min. This finding may help to enhance CA production by optimizing the fermentation medium and genetic manipulation of Streptomyces clavuligerus. It may also facilitate the structural and mechanistic studies on N2-(2-carboxyethyl)-L-arginine synthase that catalyzes an unusual N-C bond forming reaction.
Article Information Monascus purpureus is a fungus that had been cultured on the rice in eastern ... more Article Information Monascus purpureus is a fungus that had been cultured on the rice in eastern Asian countries since thousands years ago and used as a food for long years. The fungus produces very valuable metabolites with polyketide structure. The most important metabolite is Monacolin K, lovastatin or competitive inhibitor of 3-Hydroxy-3-Methylglutaryl-Coenzyme A reductase (an affective enzyme in cholesterol synthesis). This metabolite has various properties including reducing blood cholesterol, preventing infection, and treatment of progressive renal disease, a variety of tumors, vascular diseases and bone fractures. In this study, Monascus purpureus PTCC5303 has been used for lovastatin production in liquid fermentation. The nutritional concentrations that were significant in biomass and lovastatin production including maltose and MgSO 4 were optimized by Response Surface Methodology in a mili-bioreactor. The optimum concentration of maltose and MgSO 4 was obtained as 10 gl-1 ...
Metal ions are the main impurities of water and media ingredients used in fermentation processes.... more Metal ions are the main impurities of water and media ingredients used in fermentation processes. In this research, the effect of Ca+2, Co+2, Cu+2, Fe+2, Mg+2, Mn+2 and Zn+2 as chloride and sulfate salts was studied on the clavulanic acid production and Streptomyces clavuligerus growth. All chloride salts had negative effect on clavulanic acid production and no clavulanic acid was produced in the media containing more than 1.5 mM ZnCl2 and 18 mM FeCl2. CuCl2 and CaCl2 increased biomass production, while the other chloride salts decreased it. Concentration of clavulanic acid in the 0.2 mM MnSO4 containing medium was 1.21 times more than that of control. There was no significant difference in antibiotic concentration in the medium containing 0.41 mM MgSO4 and control. Other sulfate salts decreased antibiotic production. MgSO4, CuSO4 and FeSO4 increased the biomass, while other sulfate salts decreased it. Minimum and maximum specific consumption rate of glycerol were seen in the medium...
Behnoosh Sadat Khalili 1 , Javad Hamedi 2, 3* , Setareh Haghighat 1. Department of Microbiology, ... more Behnoosh Sadat Khalili 1 , Javad Hamedi 2, 3* , Setareh Haghighat 1. Department of Microbiology, Faculty of Advanced Sciences and Technologies, Pharmaceutical Sciences Branch, Islamic Azad University, Tehran, Iran. 2. Department of Microbial Biotechnology, School of Biology and Center of Excellence in Phylogeny of Living Organisms, College of Science, University of Tehran, Tehran, Iran. 3. Microbial Technology and Products Research Center, University of Tehran, Tehran, Iran.
Monascus purpureus is a fungus that had been cultured on the rice in eastern Asian countries sinc... more Monascus purpureus is a fungus that had been cultured on the rice in eastern Asian countries since thousands years ago and used as a food for long years. The fungus produces very valuable metabolites with polyketide structure. The most important metabolite is Monacolin K, lovastatin or competitive inhibitor of 3-Hydroxy-3-Methylglutaryl-Coenzyme A reductase (an affective enzyme in cholesterol synthesis). This metabolite has various properties including reducing blood cholesterol, preventing infection, and treatment of progressive renal disease, a variety of tumors, vascular diseases and bone fractures. In this study, Monascus purpureus PTCC5303 has been used for lovastatin production in liquid fermentation. The nutritional concentrations that were significant in biomass and lovastatin production including maltose and MgSO4 were optimized by Response Surface Methodology in a mili-bioreactor. The optimum concentration of maltose and MgSO4 was obtained as 10 g l-1 and 0.78 g l-1, respe...
Lipases are the biocatalysts with outstanding prospects in industry and medicine. They have prove... more Lipases are the biocatalysts with outstanding prospects in industry and medicine. They have proven to be useful in various hydrolytic and synthetic reactions. However, there are some limitations for impure lipases that may restrict their widely uses in industrial applications. Purification is sometimes vital for the characterization of the function, structure, and interactions of lipases. The lipase immobilization is also an efficient strategy for increasing the enzyme activity and stability, and getting a simpler recovery. Lipases are naturally produced together with many other proteins that they may occupy some surface of immobilization solid support and decrease the final activity. The coupling of immobilization and purification of lipase will overcome the mentioned problems and obtain the maximum purification yields. The present mini-review will discuss the use of the techniques that permit to join immobilization and purification of lipases in a single step, including control of...
IJMM 1394; 9(4): 63-72 Background and Aim: Environmental pollution by petroleum compounds have tu... more IJMM 1394; 9(4): 63-72 Background and Aim: Environmental pollution by petroleum compounds have turned into one of the global concerns. The aim of the present research was evaluation of the indigenous fungal strains of Iran to remove crude oil pollutants. Materials and Methods: First, the contaminated soil samples were collected. The samples were enriched in minimal salts medium (MSM) medium with 1% crude oil and chloramphenicol for 3 weeks and the isolates were purified. The crude oil degradation was measured by total petroleum hydrocarbon (TPH) assay method at 420 nm. In order to confirm the amount of oil degradation by selected isolate, the residual hydrocarbon content was evaluated by FTIR. Laccase activity in the presence of 1% crude oil was measured. Finally, the selected isolate was identified using morphological and molecular methods.
Production of extracellular amylase was demonstrated under conditions of high salinity in aerobic... more Production of extracellular amylase was demonstrated under conditions of high salinity in aerobically cultivated culture of a newly isolated moderately halophilic Gram-positive coccus, designated strain F in basal medium containing peptone from meat, yeast extract, NaCl (7% w/v) and starch. Biochemical and physiological characterization along with 16S rRNA sequence analysis placed F in the genus Nesterenkonia. The enzyme production was synchronized bacterial growth and reached a maximum level during the early-stationary phase in the basal medium. Maximum yield production was observed when the soluble starch, yeast extract and NaCl (1%, 0.75% and 10% w/v, respectively) were used in the fermentation medium with pH 8.0, inoculated with 7% (v/v) pre-culture medium and incubated in 30°C for 72 h with aeration of 250 rpm (299.25 U/ml). The potential of different carbohydrates in amylase production was in the order: starch> maltose>dextrin>fructose>lactose=glucose>sodium ace...
Exopolymers (EPS) are high-molecular-weight polymers secreted by some micro-organisms and have se... more Exopolymers (EPS) are high-molecular-weight polymers secreted by some micro-organisms and have several applications in food, pharmaceutical, packaging and agricultural industries, as well as medicine. Actinobacteria are valuable bacteria in biotechnology and many commercial drugs such as antibiotics, antioxidants and immune-suppressant agents are derived from Actinobacteria. Recently, their other capabilities such as exopolymer production have been taken into consideration. Due to the high potential of actinobacteria in producing various compounds and increased prevalence of infections by antibiotic-resistant pathogens, the aim of the present study was to evaluate the potential of isolated Actinobacteria from various locations of Iran to produce EPS with antimicrobial activity. Appropriate dilutions of the samples were, therefore, cultured in ISP2 medium after treatment. The isolates were primarily identified by morphological tests. Then, their ability to produce EPS was investigate...
Background and Objectives: Streptomyces tendae is one of the most prolific actinobacteria with a ... more Background and Objectives: Streptomyces tendae is one of the most prolific actinobacteria with a wide range of biotechnological applications. Genomic data can help in better understanding and exploration of important microorganisms, however, there is a few genomic information available for this species. Materials and Methods: Molecular identification, pH and salt tolerance of an actinobacterium, designated Streptomyces tendae UTMC 3329, isolated from a tea field soil were done. Also, genomic DNA was extracted and sequenced using Illumina platform with MPS (massively parallel sequencing) Illumina technology. Gene annotation and bioinformatic analysis were done using appropriate software and servers. Results: The draft genome is ~8.7 megabase pairs, containing 7557 predicted coding sequences. The strain was able to grow at pH 5-12 and 0-10% NaCl. The maximum growth rate of the bacterium was obtained at pH 7. The gene clusters involved in central carbon metabolism, phosphate regulation...
Transcription is of the most crucial steps of gene expression in bacteria, whose regulation guara... more Transcription is of the most crucial steps of gene expression in bacteria, whose regulation guarantees the bacteria’s ability to adapt to varying environmental conditions. Discovering the molecular basis and genomic principles of the transcriptional regulation is thus one of the most important tasks in cellular and molecular biology. Here, a comprehensive phylogenetic footprinting framework was implemented to predict maximal regulons of Lactococcus lactis subsp. lactis IO-1, a lactic acid bacterium known for its high potentials in nisin Z production as well as efficient xylose consumption which have made it a promising biotechnological strain. A total set of 321 regulons covering more than 90% of all the bacterium’s operons have been elucidated and validated according to available data. Multiple novel biologically-relevant members were introduced amongst which arsC, mtlA and mtl operon for BusR, MtlR and XylR regulons can be named, respectively. Moreover, the effect of riboflavin on...
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