• Microbiology and Biotechnology Letters
• /
• v.30 no.1
• /
• pp.33-38
• /
• 2002

Purification and characterization of enzyme property of a cell-wall lytic enzyme against Lactobacillus plantarum were carried out. Final specific activity of purified enzyme was 5.8 units/mg and purity of the enzyme was increased 8.3 fold compared with the enzyme activity in culture broth. The molecular weight of purified enzyme was estimated to be 60,000 kDa by gel filtration and SDS-polyacrylamide gel electrophoresis. Optimal pH and temperature for the activity of this enzyme were 3.0 and 4$0^{\circ}C$, respectively. The cell-wall lytic enzyme activity was maintained at 3$0^{\circ}C$ when treating the enzyme for 30 mins, whereas the activity was decreased to 80% of the maximum level at 4$0^{\circ}C$ The enzyme activity exhibited good stability at the range of pH 4~7.

• Korean Journal of Food Science and Technology
• /
• v.29 no.5
• /
• pp.1021-1027
• /
• 1997

We examined some properties of yeast cell wall lytic enzyme produced by Dicyma sp. YCH-37. Several metal ions, reducing reagents, and chemical modifiers have little effects on the lytic activity, except guanidine-HCl. Yeast cells of early log phase were more susceptible to the enzyme than those of stationary phase, and heat-treated cells were more easily lysed than intact living ones. Yeast cells pretreated with organic solvents such as butanol and acetone were more susceptible to the enzyme than intact living ones. Yeast cells cultured in Yeast extract-Malt extract medium containing 0.5 M ammonium sulfate were easily lysed by the lytic enzyme, and yeast cells cultured without shaking were more easily lysed by the enzyme than those with shaking. When SDS, ${\beta}-mercaptoethanol$, Triton X-100, sodium sulfite, and KCl were added to enzyme reaction mixture each, lysis of yeast cells was more effective.

• Journal of Microbiology and Biotechnology
• /
• v.16 no.10
• /
• pp.1613-1621
• /
• 2006

Isolation and identification of algal lytic bacteria were carried out. Nine strains of algal lytic bacteria were isolated by the double-layer method using Anabaena flos-aquae as a sole nutrient. The isolate, AFK-13, showing the highest algal lytic activity was identified as Sinorhizobium kostiense based on the l6S rDNA sequence. The algal lytic experiments of the culture supernatants of AFK-13 demonstrated that the bacterial cell growth reached a maximum at 36-h culture, but the supernatant of 72-h culture exhibited the highest activity. Components among the extracellular products in the crude enzyme of the supernatant from S. kostiense AFK-13 culture were responsible for degradation of cell walls of Anabaena flos-aquae. Algal lytic assay tests of the culture supernatants suggest that the main substances for algal lytic activity could be proteinaceous. The activity of glucosidase was observed highly by polysaccharolytic analysis using the crude enzyme from S. kostiense AFK-13, whereas activities of galactosidase, mannosidase, rhamnosidase, and arabinosidase were also detected in low levels. The molecular weights (MW) of ${\alpha}-\;and\;{\beta}$-glucosidases were estimated to be approximately 50-100 kDa by the ultrafiltration method.

• Microbiology and Biotechnology Letters
• /
• v.13 no.2
• /
• pp.137-144
• /
• 1985

Studies were conducted on the conditions for preparation of yeast protoplasts utilizing Hansenula anomala var. anomala FRI YO-32 as well as Saccharomyces cerevisiae KFCC 32356 and a lytic enzyme from the snail Helix pomatia. The cell wails of the strain FRI YO-32 and S cerevisiae were found to be resistant to activity of the snail lytic enzyme if they were not treated with thiol compounds. Dithiothreitol was found to be more effective than 2-mercaptoethanol, but the latter was considered to be practical. As factors influencing the formation of yeast protoplast, it was considered to be concentration and incubation time of 2-mercaptoethanol or the lytic enzyme, growth stages in yeast cultivation, initial number of yeast cells, and concentration of osmotic stabilizer (KCI). Optimum conditions for the preparation of yeast protoplasts were determined.

• KSBB Journal
• /
• v.24 no.6
• /
• pp.579-583
• /
• 2009

The effects of cell lytic enzyme treatment on total phenolic content, antioxidant and antityrosinase activities of lotus leaf were investigated. The dried lotus leaves were hydroyzed by cell lytic enzymes such as Promozyme, Ceremix, Pectinex, Ultraflo, Celluclast, Pentopan, Tunicase, Viscozyme at their optimum pHs (pH 5-8) at $50^{\circ}C$ for 4 hrs. Depending on the enzymes used, total phenolic compounds content was measured as $1,079-1,476{\mu}g$/mL, and antioxidant activities and whitening activities were increased by 5~10% and 20%, respectively Among the tested hydrolytic enzymes, Promozyme (pullulanase) was selected as the most suitable enzyme for the extraction of total polyphenol from lotus leaf. The optimal dosage of Promozyme were found to be 1-2% (w/w). By Promozyme treatment, total phenolic compounds content of the lotus extract significantly increased compared to the extraction without enzyme treatment.

• Korean Journal of Microbiology
• /
• v.21 no.4
• /
• pp.213-220
• /
• 1983

Conditions for isolation of protoplasts from conidiospores of Trichoderma koningii ATCC 26113 were tested. Maximum production of conidial protoplasts was obtained by preincubation of conidiospores on liquid minimal medium for 8 1/2 hrs. and by reaction with cell wall lytic enzyme for 3 hrs. Among effective cell wall lytic enzymes (Driselase, p-Glucuronidase, Novozyme and Zymolyase), Driselase was the most effective one on the production of conidial protoplasts. The production of conidial protoplasts was also enhanced by addition of 2-Deoxy-D-Glucose $(25{\mu}g/ml)$ into liquid minimal medium. Over 70% of the initial swollen conidia, preincubated in liquid minimal medium supplemented with 2-Deoxy-D-Glucose $(25{\mu}g/ml)$, were converted to protoplasts by incubation with 2% (w/v) commercial lytic enzyme Driselase at $28^{\circ}C$ for 3 hrs. The reversion frequency of the conidial protoplasts was about 30 times (25-50%) higher than that of mycelial protoplasts (0.6-1.3%).

• Korean Journal of Environmental Biology
• /
• v.22 no.1
• /
• pp.184-191
• /
• 2004

To investigate bacteria with algalytic activities against Anabaena cylindrica when water blooming occurs and to study enzyme profiles associated with alga-lytic activity, various bacterial strains were isolated from surface waters and sediments in eutrophic lakes or reservoirs in Korea. Among 178 isolates, only nine isolates exhibited lytic abilities against A cylindrica on the agar plates, and then the isolate AK-13 was selected as the strongest in lysing the cyanobacterium A. cytindrica. The strain AK-13 was characterized and identified as Sinorhizobium sp. based on fatty acid methyl ether profiles and 16S rDNA sequence. According to the results of the enzyme assays, in the strain An-13 of Sinorhizobium sp., alginase, amylase, proteinase (caseinase and gelatinase), carboxymethyl-cellulase (CMCase), laminarinase, and lipase was produced, namely CMCase, laminarinase and protease were highly active. None of glycosidase was produced. Therefore, enzyme systems of Sinorhizobium sp. AK-13 were very complex to degrade cell walls of A. cylindrica. The peptidoglycans of A. cylindrica mat be hydrolyzed and metabolized to a range of easily utilizable monosaccharides or other low molecular weight organic substances by Sinorhizobium sp. AK-13.

• Journal of Applied Biological Chemistry
• /
• v.63 no.4
• /
• pp.291-295
• /
• 2020

In order to increase the utilization of defatted sesame meal (DSM), a by-product of sesame oil production, the conditions of extraction of insoluble proteins from DSM by enzyme treatment were investigated. As a result of comparing the treatment results of proteolytic enzymes Alcalase, Flavorzyme, Neutrase, and Protamex with control, Protamex was effective in increasing the total solid and protein content. At the reaction conditions of Protamex (50 ℃, pH 6.0), the dosage of enzymes was appropriate for 1% of DSM and 3 h of enzyme reaction time. To improve the efficiency of enzymatic treatment, the protein content extracted increased as the heat treatment temperature increased, and slightly increased above 110 ℃. As a result of investigating the effect of the combination treatment of cell lytic enzyme (Tunicase) and protease (Protamex) on protein solubilization, it was most effective to treat the cell lytic enzyme after processing the protease. After heat treatment (110 ℃, 10 min), sequential treatment of Protamex and Tunicase increased the protein content by about 3.5 times (9.85→35.58 mg/mL) of the non-heated control and 2.2 times (15.83→35.58 mg/mL) of the heat treated control.

• Journal of Microbiology and Biotechnology
• /
• v.5 no.4
• /
• pp.206-212
• /
• 1995

A strain BL-29, which produces a extracellular lytic enzyme on E. coli was isolated from the soil. The strain was identified as belonging to the genus Bacillus sp. The lytic enzyme was purified to homogeneity by ion exchange chromatography and gel filtration. Specific activity of the purified enzyme was 28, 850 U/mg protein and yield of the enzyme was 5$%$. The purified enzyme showed a single band on SDS-PAGE and its molecular weight was estimated to be 31, 000 by SDS-polyacrylamide gel electrophoresis and gel filtration column chromatography. The optimum temperature and pH were $55^{\circ}C$ and pH 10.0, respectively. The enzyme was stable at $45^{\circ}C$ but enzyme activity was reduced by up to 50$%$ when the temperature was raised to $55^{\circ}C$ for 15 min. Stable range of pH was from 5.0 to 11.0. but Enzyme activity was inhibited by lead-acetate, mercuric chloride, ethylene glycol-bis-[$\beta$-aminoethyl ether]-N, N, $N^1, $N^1$-tetraacetic acid (EGTA), and ethylenediamine tetraacetic acid (EDTA), but not affected considerably by treatment with other chemical reagents.

• Korean Journal of Food Science and Technology
• /
• v.35 no.6
• /
• pp.1143-1149
• /
• 2003

To elucidate a method of preventing dental caries, strains producing lytic enzymes were isolated and their characteristics were investigated. Among 5,00 alkalophilic strains isolated from soil, 22 strains showed lytic activity against Streptococcus mutans. Strain No. 4830, with the highest lytic activity, was selected for further study. Strain 4830 showed 94% sequence homology with the 16S rDNA sequence of Bacillus alcalophilus, but it was concluded to be different from Bacillus alcalophilus because of its biochemical characteristics. The strain was named Bacillus sp. 4830. The lytic enzyme from Bacillus sp. 4830 was purified by ethanol precipitation and CM-agarose column chromatography. The molecular weight of the lytic enzyme was determined to be 28 kDa by SDS-PAGE. The lytic enzyme was stable between pH 5.0 and pH 11 and up to $40^{\circ}C$. The optimal pH and temperature for the lytic activity was 9.0 and $50^{\circ}C$, respectively.