scholarly journals Genetic Modification of mfsT Gene Stimulating the Putative Penicillin Production in Monascus ruber M7 and Exhibiting the Sensitivity towards Precursor Amino Acids of Penicillin Pathway

2019 ◽  
Vol 7 (10) ◽  
pp. 390
Author(s):  
Ramzan ◽  
Safiullah Virk ◽  
Muhammad ◽  
Ahmed ◽  
Yuan ◽  
...  

: The biosynthesis of penicillin G (PG) is compartmentalized, which forces penicillin and its intermediates to cross the membrane barriers. Although many aspects around the penicillin intermediates traffic system remain unclosed, the transmembrane transporter protein involvement has been only predicted. In the present work, detection of PG and isopenicillin N (IPN) in Monascus ruber M7 was performed and functions of mfst gene as a transporter were investigated by the combination of gene deletion (Δmfst) complementation (ΔmfsT::mfsT) and overexpression (M7::PtrpC-mfsT). While, the feeding of PG pathway precursor side chain and amino acids, i.e., phenylacetic acid, D-valine, and L-cysteine was performed for the interpretation of mfsT gene role as an intermediate transporter. The results showed that, the feeding of phenylacetic acid, D-valine, and L-cysteine possessed a significant effect on morphologies, secondary metabolites (SMs) production of all above-mentioned strains including M. ruber M7. The results of UPLC-MS/MS revealed that, ΔmfsT interrupt the penicillin G (PG) production in M. ruber M7 by blocking the IPN transportation, while PG and IPN produced by the ΔmfsT::mfsT have been recovered the similar levels to those of M. ruber M7. Conclusively, these findings suggest that the M. ruber M7 is, not only a PG producer, but also, indicate that the mfsT gene is supposed to play a key role in IPN intermediate compound transportation during the PG production in M. ruber M7.

2020 ◽  
Vol 6 (3) ◽  
pp. 156
Author(s):  
Li Li ◽  
Fusheng Chen

Monascus pigments (MPs) have been used as food colorants for several centuries in Asian countries and are now used throughout the world via Asian catering. The MP biosynthetic pathway has been well-illustrated, but the functions of a few genes, including mrpigG, in the MP gene cluster are still unclear. In the current study, in order to investigate the function of mrpigG in M. ruber M7, gene deletion (ΔmrpigG), complementation (ΔmrpigG::mrpigG) and overexpression (M7::PtrpC-mrpigG) mutants were successfully obtained. The morphologies and biomasses, as well as the MP and citrinin production, of these mutants were analyzed. The results revealed that the disruption, complementation and overexpression of mrpigG showed no apparent defects in morphology, biomass or citrinin production (except MP production) in ΔmrpigG compared with M. ruber M7. Although the MP profiles of ΔmrpigG and M. ruber M7 were almost the same—with both having four yellow pigments, two orange pigments (OPs) and two red pigments (RPs)—their yields were decreased in ΔmrpigG to a certain extent. Particularly, the content of rubropunctatin (an OP) and its derivative rubropunctamine (an RP) in ΔmrpigG, both of which have a five-carbon side chain, accounted for 57.7%, and 22.3% of those in M. ruber M7. On the other hand, monascorubrin (an OP) and its derivative monascorubramine (an RP), both of which have a seven-carbon side chain, were increased by 1.15 and 2.55 times, respectively, in ΔmrpigG compared with M. ruber M7. These results suggest that the MrPigG protein may preferentially catalyze the biosynthesis of MPs with a five-carbon side chain.


1994 ◽  
Vol 49 (11-12) ◽  
pp. 834-842 ◽  
Author(s):  
Dierk Martin ◽  
Eckhard Schlimme

The hypermodified ureidonucleoside N6[((9-β-ᴅ-ribofuranosyl-9H-purine-6-yl)amino)carbonyl]- ʟ-threonine (5) is a constituent of transfer ribonucleic acid (tRNA) and is secreted as a tRNA catabolite in body fluids such as blood, milk and urine. Compound 5 and the isomeric ureidonucleosides bearing ᴅ-threonine (9), ʟ-allo- (7) and ᴅ-allo-threonine (11) as side chain moieties were synthesized on a preparative scale. The amido protons of 5 and 9 cause two separate 1H NMR signals whereas 7 and 11 cause multiplets. The 13C NMR signals of all carbon atoms of the allo-amino acid side chains (7, 11) are shifted downfield of the corresponding signals in compounds 5 and 9. The chemically protected intermediate compound adenosine urethane (3) is potentially of interest in the analysis of amino acids because it may be converted to nucleosides of the ureido type by reaction with amino acids in biological matrices.


1980 ◽  
Vol 45 (2) ◽  
pp. 482-490 ◽  
Author(s):  
Jaroslav Vičar ◽  
François Piriou ◽  
Pierre Fromageot ◽  
Karel Bláha ◽  
Serge Fermandjian

The diastereoisomeric pairs of cyclodipeptides cis- and trans-cyclo(Ala-Ala), cyclo(Ala-Phe), cyclo(Val-Val) and cyclo(Leu-Leu) containing 85% 13C enriched amino-acid residues were synthesized and their 13C-13C coupling constants were measured. The combination of 13C-13C and 1H-1H coupling constants enabled to estimate unequivocally the side chain conformation of the valine and leucine residues.


Synlett ◽  
2019 ◽  
Vol 30 (11) ◽  
pp. 1289-1302 ◽  
Author(s):  
Phil Servatius ◽  
Lukas Junk ◽  
Uli Kazmaier

Peptide modifications via C–C bond formation have emerged as valuable tools for the preparation and alteration of non-proteinogenic amino acids and the corresponding peptides. Modification of glycine subunits in peptides allows for the incorporation of unusual side chains, often in a highly stereoselective manner, orchestrated by the chiral peptide backbone. Moreover, modifications of peptides are not limited to the peptidic backbone. Many side-chain modifications, not only by variation of existing functional groups, but also by C–H functionalization, have been developed over the past decade. This account highlights the synthetic contributions made by our group and others to the field of peptide modifications and their application in natural product syntheses.1 Introduction2 Peptide Backbone Modifications via Peptide Enolates2.1 Chelate Enolate Claisen Rearrangements2.2 Allylic Alkylations2.3 Miscellaneous Modifications3 Side-Chain Modifications3.1 C–H Activation3.1.1 Functionalization via Csp3–H Bond Activation3.2.2 Functionalization via Csp2–H Bond Activation3.2 On Peptide Tryptophan Syntheses4 Conclusion


Fuel ◽  
2021 ◽  
Vol 299 ◽  
pp. 120828
Author(s):  
Kan Jeenmuang ◽  
Chakorn Viriyakul ◽  
Katipot Inkong ◽  
Hari Prakash Veluswamy ◽  
Santi Kulprathipanja ◽  
...  

Author(s):  
Dong-Xu Jia ◽  
Chen Peng ◽  
Jun-Liang Li ◽  
Fan Wang ◽  
Zhi-Qiang Liu ◽  
...  

1933 ◽  
Vol 8 (5) ◽  
pp. 447-449 ◽  
Author(s):  
Steward Basterfield ◽  
James W. Tomecko

The ionization constants of p-nitrophenylacetic and phenylmalonic acids have been determined from conductivity data. The value of K for p-nitrophenylacetic acid at 25 °C. is 1.04 × 10−4, about twice that of phenylacetic acid. The nitro group in the nucleus has not as powerful an effect on the ionization when the COOH group is in the side chain as it has when both nitro group and COOH are in the nucleus. K for p-nitrobenzoic acid is six times as great as K for benzoic acid. K for phenylmalonic acid is 2. 77 × 10−3 as compared with 1.6 × 10−3 for malonic acid.


2013 ◽  
Vol 405 ◽  
pp. 121-127 ◽  
Author(s):  
Jaromír Vinklárek ◽  
Jan Honzíček ◽  
Milan Erben ◽  
Iva Klepalová ◽  
Aleš Eisner ◽  
...  

Tetrahedron ◽  
2000 ◽  
Vol 56 (16) ◽  
pp. 2513-2522 ◽  
Author(s):  
Zhenyu Zhang ◽  
Arthur Van Aerschot ◽  
Chris Hendrix ◽  
Roger Busson ◽  
Frank David ◽  
...  
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