Mamoru Komatsu

Learn More
To construct a versatile model host for heterologous expression of genes encoding secondary metabolite biosynthesis, the genome of the industrial microorganism Streptomyces avermitilis was systematically deleted to remove nonessential genes. A region of more than 1.4 Mb was deleted stepwise from the 9.02-Mb S. avermitilis linear chromosome to generate a(More)
Actinophage TG1 forms stable lysogens by integrating at a unique site on chromosomes of Streptomyces strains. The phage (attP(TG1)) and bacterial (attB(TG1)) attachment sites for TG1 were deduced from comparative genomic studies on the TG1-lysogen and nonlysogen of Streptomyces avermitilis. The attB(TG1) was located within the 46-bp region in the dapC gene(More)
Certain streptomycin resistance mutations (i.e., rpsL and rsmG) result in the overproduction of antibiotics in various actinomycetes. Moreover, rpsL rsmG double-mutant strains show a further increase in antibiotic production. rpsL but not rsmG mutations result in a marked enhancement of oligomycin production in Streptomyces avermitilis and erythromycin(More)
We have previously shown that, in vivo, the integration system based on the gene encoding the TG1 integrase and the corresponding attB TG1 and attP TG1 sites works well not only in Streptomyces strains, but also in Escherichia coli. Furthermore, the attachment sites for TG1 integrase are distinct from those of ϕC31 integrase. In this report, we expressed(More)
The γ-butyrolactone autoregulator receptor has been shown to control secondary metabolism and/or morphological differentiation across many Streptomyces species. Streptomyces avermitilis produces an important anthelmintic agent (avermectin) and two further polyketide antibiotics, filipin and oligomycin. Genomic analysis of S. avermitilis revealed that this(More)
An industrial microorganism, Streptomyces avermitilis, which is a producer of anthelmintic macrocyclic lactones, avermectins, has been constructed as a versatile model host for heterologous expression of genes encoding secondary metabolite biosynthesis. Twenty of the entire biosynthetic gene clusters for secondary metabolites were successively cloned and(More)
To identify the genes for biosynthesis of the off-flavor terpenoid alcohol, 2-methylisoborneol (2-MIB), the key genes encoding monoterpene cyclase were located in bacterial genome databases by using a combination of hidden Markov models, protein-family search, and the sequence alignment of their gene products. Predicted terpene cyclases were classified into(More)
Pentalenic acid (1) has been isolated from many Streptomyces sp. as a co-metabolite of the sesquiterpenoid antibiotic pentalenolactone and related natural products. We have previously reported the identification of a 13.4-kb gene cluster in the genome of Streptomyces avermitilis implicated in the biosynthesis of the pentalenolactone family of metabolites(More)
Streptomyces coelicolor A3(2) retains unique conserved operons termed conservons. Here, one of the conservons (cvn9), which encodes five proteins (A9-E9), was characterized. Mutants for cvnA9 and cvnAlO conditionally overproduced actinorhodin and performed precocious aerial growth, while a cvnE9 mutant showed the parental phenotype. Transcription of bidG,(More)
Mycosporines and mycosporine-like amino acids (MAAs), including shinorine (mycosporine-glycine-serine) and porphyra-334 (mycosporine-glycine-threonine), are UV-absorbing compounds produced by cyanobacteria, fungi, and marine micro- and macroalgae. These MAAs have the ability to protect these organisms from damage by environmental UV radiation. Although no(More)