Optimal Central Composite Designs for Fitting Second Order Response Surface Linear Regression Models

Abstract

A novel Gram-positive, strictly aerobic and non-motile bacterial strain, S6-4 T, was isolated from a Korean alcohol fermentation starter. Optimal growth occurred at 37 °C, at pH 8 and in 1% (w/v) NaCl. The isolate was positive for oxidase and catalase. It assimilated various sugars and acids were produced from several carbohydrates. The major cell-wall sugars were galactose and arabinose. The major fatty acids of strain S6-4 T were C 16: 0, C 17: 1ω9c, C 18: 1ω9c and 10-methyl C 18: 0 (tuberculostearic acid). The predominant isoprenoid quinone was menaquinone MK-9(H 2) and peptidoglycan amino acids were meso-diaminopimelic acid, alanine, glycine and glutamic acid. The strain contained mycolic acids. According to phylogenetic analysis based on 16S rRNA gene sequences, strain S6-4T was most closely related to Corynebacterium variabile DSM 20132 T (98.1% similarity). The genomic DNA G+C content of strain S6-4 T was 73.6 mol% and DNA-DNA hybridization values with related strains were below 33±4%. On the basis of phenotypic, genotypic and phylogenetic data, strain S6-4T represents a novel species in the genus Corynebacterium, for which the name Corynebacterium nuruki sp. nov. is proposed; the type strain is S6-4 T (=KACC 15032 T =JCM 17162 T). © 2011 IUMS.