Phytases from Enterobacter and Serratia species with desirable characteristics for food and feed applications
نویسندگان
چکیده
Phytases are enzymes of great industrial importance with wide range of applications in animal and human nutrition. These catalyze the hydrolysis of phosphomonoester bonds in phytate, thereby releasing lower forms of myo-inositol phosphates and inorganic phosphate. Addition of phytase to plant-based foods can improve its nutritional value and increase mineral bioavailability by decreasing nutritional effect of phytate. In the present investigation, 43 phytase positive bacteria on PSM plates were isolated from different sources and characterized for phytase activity. On the basis of phytase activity and zone of hydrolysis, two bacterial isolates (PSB-15 and PSB-45) were selected for further characterization studies, i.e., pH and temperature optima and stability, kinetic properties and effect of modulators. The phytases from both isolates were optimally active at the pH value from 3 to 8 and in the temperature range of 50-70 °C. Further, the stability of isolates was good in the pH range of 3.0-8.0. Much variation was observed in temperature and storage stability, responses of phytases to metal ions and modulators. The K m and V max values for PSB-15 phytase were 0.48 mM and 0.157 μM/min, while for PSB-45 these were 1.25 mM and 0.140 μM/min, respectively. Based on 16S rDNA gene sequence, the isolates were identified as Serratia sp. PSB-15 (GenBank Accession No. KR133277) and Enterobacter cloacae strain PSB-45 (GenBank Accession No. KR133282). The novel phytases from these isolates have multiple characteristics of high thermostability and good phytase activity at desirable range of pH and temperature for their efficient use in food and feed to facilitate hydrolysis of phytate-metal ion complex and in turn, increased bioavailability of important metal ions to monogastric animals.
منابع مشابه
Molecular Characterization and Comparative Phylogenetic Analysis of Phytases from Fungi with Their Prospective Applications
Plant seeds that have high phytate content are used as animal feed. Phytases, enzymes that catalyze the breakdown of phytate into inorganic phosphorus and myoinositol phosphate derivatives, have been intensively studied in recent years and gained immense attention because of their application in reducing phytate content in animal feed and food for human consumption, thus indirectly lowering env...
متن کاملGRAM NEGATIVE BACILLI IN BURNS
In a period of nine months, 225 strains of Gram-negative bacilli isolated from burns were identified by a variety of tests in two burn centers in Tehran. The most common species were Pseudomonas aeruginosa, Pseudomonas fluorescens, Escherichia coli, Enterobacter agglomerans, Enterobacter cloacae and Klebsiella pneumoniae. Many strains of acinetobacter spp, providencia spp, proteus spp, ser...
متن کاملEvolution of the gyrB gene and the molecular phylogeny of Enterobacteriaceae: a model molecule for molecular systematic studies.
Phylogenetic trees showing the evolutionary relatedness of Enterobacteriaceae based upon gyrB and 16S rRNA genes were compared. Congruence among trees of these molecules indicates that the genomes of these species are not completely mosaic and that molecular systematic studies can be carried out. Phylogenetic trees based on gyrB sequences appeared to be more reliable at determining relationship...
متن کاملBacterial Phytase: Potential Application, in Vivo Function and Regulation of Its Synthesis
The stepwise release of phosphate from phytate, the major storage form of phosphate in plant seeds and pollen, is initiated by a class of enzymes that have been collectively called phytases. The classification is solely due to the in vitro capability of these enzymes to accept phytate as a substrate. Phytases have been studied intensively in recent years because of the great interest in such en...
متن کاملExistance of Microbial Species in Vermicomposts Derived from Mixed Sesame Crust and Cow Manure Treatments
Introduction: The presence of pathogenic microbial agents and pathogens in organic fertilizers causes health problems and disease transmission.Therefore , the aim of this study was to identify bacterial and fungal species present in vermicompost production. Materials and Methods: This experimental study was conducted in pilot scale in the laboratory of Public Health School in Shahid Sadoughi U...
متن کامل