The aim of this study was to isolate chicken feather-degrading bacteria with high keratinolytic activity and to investigate cultural conditions affecting keratinolytic enzyme production by a selected isolate. A chicken feather-degrading bacterial strain CH3 was isolated from poultry wastes. Isolate CH3 degraded whole chicken feather completely within 3 days. On the basis of phenotypical and 16S rDNA studies, isolate CH3 was identified as Bacillus thuringiensis CH3. This strain is the first B. thuringiensis described as a feather degrader. The bacterium grew with an optimum at pH 8.0 and 37℃, where maximum keratinolytic activity was also observed. The composition of optimal medium for keratinolytic enzyme production was feather 0.1%, sucrose 0.7%, casein 0.3%, K2HPO4 0.03%, KH2PO4 0.04%, MgCl2 0.01% and NaCl 0.05%, respectively. The keratinolytic enzyme had a pH and temperature optima 9.0 and 45℃, respectively. The keratinolytic activity was inhibited ethylenediaminetetraacetic acid, phenylmethylsulfonyl fluoride, and metal ions like Hg2+, Cu2+ and Zn2+. The enzyme activated by Fe2+, dithiothreitol and 2-mercaptoethanol.

‘Taegang’ is a new six-rowed covered barley cultivar developed by the National Institute of Crop Science (NICS), R.D.A. This cultivar is developed from a cross between ‘Suwon287’ and ‘Olbori’ in 1992. An F8 selection was made at NCES in 2000 and it was te

Two important loci, designated Rhg1 and Rhg4, are responsible for most resistance to soybean cyst nematode (SCN). The objective of this study was to survey single nucleotide polymorphism (SNP) and to map the SCN-resistant gene, Rhg4, on soybean genetic ma

“Jaeanchal” is a new six-rowed, naked and waxy barley cultivar developed by National Crop Experiment Station (NCES), RDA in 2001. This cultivar was derived from a cross between “Suwon261” and “SB881115-6” in 1989. The final selection was made at NCES in 1

A new two-rowed naked waxy barley cultivar, 'Pungsanchal', was developed for split polished grains by the National Crop Experiment Station(NCES), RDA in 2001. This cultivar was derived f rom a cross between 'SB901258GG-B' and 'Suwon212' in 1991. The f ina

To evaluate the efficiency of anther floating culture according to the maturing group, the varietal difference and classification of fifty varieties was conducted in N6 liquid medium containing 1mg l-1 NAA, 0.25 mg l-1 kinetin. The efficiency of callus induction was widely ranged from 0 to 113.4%, but the mean callus induction was not significantly different among maturing groups. The efficiency of anther floating culture showed the highest variation in early-maturing group among three maturing groups. The varieties with the best callus induction were Sambaegbyeo and Jinbuolbyeo, while the recalcitrant variety was Obongbyeo in early-maturing group. The efficiency of plant regeneration showed the highest trends in late-maturing group among three maturing groups. The fifty varieties were classified into three groups (distance=0.78) by cluster analysis based on the callus formation and plant regeneration. Group including only two varieties, Shinunbongbyeo and Sambaegbyeo had the excellent androgenic efficiency, and the medium efficiency of Group was included thirty-six varieties. Whereas twelve varieties, including three Tongil varieties were fell into the bad efficiency of Group. Especially, Tongil varieties containing Japonica rice, Obongbyeo were the recalcitrant genotypes for the anther floating culture.