Abstract
Egyptian soil sample was screened for isolation methioninlytic fungi by a rapid plate assay procedure. Eighteen strains of different isolated fungi were screened quantitavely for their L-methioninase activity. Chaetomium globosum was the most efficacious isolate and a dematiaceous filamentous fungi, it was identified at the molecular level by ribotyping 18S rRNA along with the biochemical characterization, and lastly completed by BLAST analysis by structure of a phylogenetic tree. Results showed that, the optimum levels of the incubation period, temperature, pH, methionine, sucrose and sodium nitrate concentrations were 3 days, 30°C, 7, 0%, 30 g/l and 1g/l, respectively. According to the produced model, at these levels, C. globosum produce L-methioninase with predicted specific activity of (≈2225 U/mg); so L-methioninase could be a good source for clinical therapeutic application. The rRNA sequence of C. globosum was deposited to gene bank under accession number KXO24450 Key words: L-methioninase, Chaetomium globosum, 18S rRNA, enzyme optimization, soil.
Highlights
L-Methioninase (E.C 4.4.1.11) is a pyridoxal phosphatedependent enzyme and is a fulfilling several functions enzyme system because it stimulates the, γ- and α, βremoval reactions of methionine and its derivatives.Physiologically, normal cells have the capability to grow on homocysteine, instate of methionine, due to their efficient methionine synthase (Mecham et al, 1983).Unlike normal cells, tumor cells freed from efficient methionine synthase rely on external methionine supplementation from the diet (Hoffman, 1984)
Chaetomium globosum was the most efficacious isolate and a dematiaceous filamentous fungi, it was identified at the molecular level by ribotyping 18S rRNA along with the biochemical characterization, and lastly completed by BLAST analysis by structure of a phylogenetic tree
Normal cells have the capability to grow on homocysteine, instate of methionine, due to their efficient methionine synthase (Mecham et al, 1983)
Summary
L-Methioninase (E.C 4.4.1.11) is a pyridoxal phosphatedependent enzyme and is a fulfilling several functions enzyme system because it stimulates the, γ- and α, βremoval reactions of methionine and its derivatives. Due to the recurrent classification of L-methioninase as extracellular enzyme in the fungal extract, fungi could be considered as robust resources to this enzyme. Our work concentrated on screening for L-methioninase-producing fungi isolated from Egyptian soil and using statistical (response surface) methodology in a trial to reduce or eliminate L-methionine from the formulated medium in parallel with optimization of the production conditions. The fungal isolates were screened for their L-methioninase productivities using qualitative rapid plate assay using the above medium and phenol red was added to the medium as indicator at final concentration of 0.007% just before pouring the plate and it incubated at 28°C for 7 days (Sundar and Nellaiah, 2013).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
