Efficient and inexpensive methods are required for the high-throughput quantification of amino acids in physiological fluids or microbial cell cultures. Here we develop an array of Escherichia coli biosensors to sensitively quantify eleven different amino acids. By using online databases, genes involved in amino acid biosynthesis were identified that - upon deletion - should render the correspo...

Polymyxin E belongs to cationic polypeptide antibiotic bearing four types of direct precursor amino acids including L-2,4-diaminobutyric acid (L-Dab), L-Leu, D-Leu, and L-Thr. The objective of this study is to evaluate the effect of addition of precursor amino acids during fermentation on polymyxin E biosynthesis in Paenibacillus polymyxa. The results showed that, after 35 h fermentation, addit...

For many bacteria with sequenced genomes, we do not understand how they synthesize some amino acids. This makes it challenging to reconstruct their metabolism, and has led to speculation that bacteria might be cross-feeding amino acids. We studied heterotrophic bacteria from 10 different genera that grow without added amino acids even though an automated tool predicts that the bacteria have gap...

Antimycins are anticancer compounds produced by a hybrid nonribosomal peptide synthetase/polyketide synthase (NRPS/PKS) pathway. The biosynthesis of these is well characterized, with the exception standalone ?-ketoreductase enzyme AntM that proposed to catalyze reduction C8 carbonyl antimycin scaffold. Inactivation antM and structural characterization suggested rather than functioning as post-P...

Phytohormones exhibit a wide range of chemical structures, though they primarily originate from three key metabolic precursors: amino acids, isoprenoids, and lipids. Specific such as tryptophan, methionine, phenylalanine, arginine, contribute to the production various phytohormones, including auxins, melatonin, ethylene, salicylic acid, polyamines. Isoprenoids are foundation five phytohormone c...

An antifungal antibiotic (S) 2-amino-4-oxo-5-hydroxypentanoic acid, inhibited the biosynthesis of the aspartate family of amino acids (methionine, isoleucine and threonine) followed by the inhibition of protein biosynthesis in Saccharomyces cerevisiae. This inhibition was effected by impeding the biosynthesis of their common intermediate precursor, homoserine. The inhibition of biosynthesis of ...

Gcn4p is a well-characterized bZIP transcription factor that activates more than 500 genes encoding amino acids and purine biosynthesis enzymes, and many stress-response genes under various stress conditions. Under these stresses, it had been shown that transcriptions of ribosomal protein (RP) genes were decreased. However, the detailed mechanism of this downregulation has not been elucidated. ...

Nocardia mediterranei produces the antibiotic rifamycin B, which belongs to the ansamycin group. The structure of rifamycin consists of the ansa chain and the chromophore. One part of this chromophore, the seven-carbon amino unit, which initiates ansa chain formation in ansamycins, has been identified as 3-amino-5-hydroxybenzoic acid. Kibby et al. 1] synthesized [carboxy-14C]3-amino-5hydroxyben...

stearoyl-coa desaturase (scd) is a rate-limiting enzyme in the biosynthesis of monounsaturated fatty acids (mufa). a number of studies support the hypothesis that scd gene regulation and polymorphism may affect fatty acid composition and fat quality in meat and milk. single nucleotide polymorphisms in the coding region of the bovine stearoyl-coa desaturase gene have been predicted to result in ...