• Journal of Microbiology and Biotechnology
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• v.5 no.1
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• pp.48-50
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• 1995

We discovered that the Bacillus licheniformis SSA3, fermenting traditional Korean soy sauce and soybean paste, involved in the synthesis of a dark-brown pigment. This pigment produced in the minimal medium supplemented with tyrosine only as precursor. We showed that this pigment is novel, and differed from melanoidin and melanin, and an antimutagenic substance.

• Mycobiology
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• v.50 no.6
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• pp.429-438
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• 2022

Two fungal strains belonging to Ascomycota were discovered in Gyeonggi-do, Korea, during this investigation of soil microfungi and microbiota of insects. The strain KNUF-20-047 produced milky white on the back and a milky creamy center to white toward the margin on the front side of colonies. Conversely, the closest Xenoacremonium falcatus displayed a pale luteous to luteous center, white toward margins on the front side, and pale luteous or luteous pigment on the back side, whereas X. recifei produced white colonies. The conidiophores of KNUF-20-047 were slightly larger than those of X. falcatus, and the conidia were distinct from X. recifei. Strain KNUF-20-NI-005 produced light brown to subhyaline conidiophores up to 56.0 lm tall, whereas Rhinocladiella anceps displayed golden to dark brown conidiophores up to 350 lm. Strain KNUF-20-NI-005 also produced larger conidia than R. anceps but smaller than R. coryli and R. fasciculata. Moreover, the molecular phylogeny strongly supports the detailed description and illustration of each proposed species to be designated as Xenoacremonium minutisporum sp. nov. and Rhinocladiella terrigenum sp. nov. in Korea.

• Applied Biological Chemistry
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• v.48 no.4
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• pp.345-351
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• 2005

To access the natural products of uncultured microorganisms, we constructed and screened the metagenomic DNA libraries by using a cosmid vector and DNA inserts isolated directly from soil. Initial screening of the libraries in Escherichia coli resulted in the isolation of several clones that produce a dark brown color when grown in LB medium. One of the positive clones, designed pYS85C, was transposon mutagenized and the DNA surrounding the transposon insertions in cosmids that no longer conferred the production of brown pigment to E. coli was sequenced. Annotation of the pYS85C sequence obtained from the transposon mutagenesis experiment indicated a single 393 amino acid open reading frame (ORF) with a molecular mass of about 44.5 kDa, predicted to be a 4-hydroxyphenylpyruvate dioxygenases (HPPDs), was responsible for the observed brown pigment. In a BLAST search against deposited sequence, the translated protein from this ORF showed moderate-level identity (>60%) to the other known HPPDs and was most conserved in the C-terminal region of the protein. These results show that genes involved in natural product synthesis can be cloned directly from soil DNA and expressed in a heterologous host, supporting the idea that this technology has the potential to provide novel natural products from the wealth of environmental microbial diversity and is a potentially important new tool for drug discovery.