• Journal of Microbiology and Biotechnology
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• v.2 no.4
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• pp.260-267
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• 1992

Pectate lyase from alkalitolerant Bacillus sp. YA-14 is an endo-type pectate lyase which acts randomly at the $\alpha$-1, 4-galacturonan linkage, and requires calcium or strontium ions for its activity. The enzyme is active on low methyl esterified pectin, but the activity toward a high methyl esterified substrate is reduced. The apparent Km's of the enzyme toward sodium polygalacturonic acid, polygalacturonic acid, and various pectins such as apple pectin, citrus pectin, and genu pectin are 0.826 mg/ml, 0.685 mg/ml, and 1.14 mg/ml, respectively. The enzyme activity is inhibited by SDS, urea, and sodium azide, but not by various reducing reagents, such as $\beta$-mercaptoethanol, Na-thiosulfate, Na-sulfate, cystein, and L-ascorbic acid. The enzyme is inactivated by N-bromosuccinimide, $I_2, H_2O_2$. PMSF, and iodoacetate. Judging from the results of their inhibition types, we speculate that tryptophan and serine residues are directly involved in enzyme activity, while tyrosine and methionine residues are indirectly involved in its activity.

• Korean Journal Plant Pathology
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• v.10 no.3
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• pp.163-168
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• 1994

Erwinia rhapontici causes soft-rot disease in a number of plants such as rhubarb, onion, hyacinth and garlic. Pectate lyase (Pel) depolymerizes pectin and other polygalacturonates, which is though to play a role in bacterial invasion of plants. Pel activity was not detected in E. rhapontici cultured in a minimal salts medium containing glycerol, polygalacturonate, or citrus pectin as a carbon source. However, when sterilized potato tuber and Chinese cabbage slices were added to minimal salts polygalacturonate (0.5%) medium, E. rhapontici produced pectate lyase enzyme. Also Pel activity was consistently detected from macerated potato tubers, Chinese cabbage leaves, lettuce leaves and celery petioles tissue. Pel in the extract of macerated Chinese cabbage caused by E. rhapontici strain 1, resulted in electrolyte loss, tissue maceration and cell death of potato tuber tissue. These results indicate that E. rhapontici produces pectate lyase only in the presence of non-diffusible plant components, and that this enzyme probably contributes to its pathogenicity.

• Journal of Microbiology and Biotechnology
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• v.8 no.4
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• pp.353-360
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• 1998

A bacterial strain PN33 producing large amounts of extracellular pectin lyase (PNL, EC 4.2.2.10) was isolated from soil. The isolated bacterium was identified as a strain of Bacillus sp. Production of PNL by the strain was induced only by pectins, with a higher degree of esterification, which had been added to the culture medium as a sole carbon source. The optimal medium for PNL production was determined to consist of 10 g pectin, 2 g yeast extract, 4 g $K_2HPO_4{\cdot}3H_2O$, 0.6 g $MgSO_4$, and 0.11 g $CaCl_2$ per liter (pH 7.0). The PNL activity in the culture supernatant reached the highest level of 132 mU/ml after 32 h cultivation at $37^{\circ}C$ in the optimal medium. The PNL produced was purified to homogeneity by ammonium sulfate fractionation (50~80%), and cation exchange and size exclusion chromatographies. The molecular mass of the enzyme was estimated to be approximately 52 kDa by SDS-PAGE. Almost the same mass was determined by nondenaturing PAGE, indicating that the functional enzyme had a monomeric structure. As expected, the PNL exhibited higher activities on the highly esterified pectins whereas it gave no detectable activity on polygalacturonic acid. The enzyme showed the highest activity at the acidic pH of 6.0, exceptional for a bacterial PNL. Maximum activity was measured at $40^{\circ}C$, although the stability f the purified enzyme was poor at this temperature. alcium (1 mM) was found to activate the PNL activity by $50\%$, and also remarkably increased the thermal stability f the enzyme. Phenylmethylsulfonylfluoride (PMSF) and iethylpyrocarbonate (DEPC) inhibited the PNL activity lmost completely at the concentration of 5 mM. This result ndicates that some serine and histidine residues of the nzyme may play an essential role for catalytic function of he enzyme.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.670-677
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• 2010

An alkaline pectate lyase, Bsp165PelA, was purified to homogeneity from the culture broth of alkaliphilic Bacillus sp. N16-5. The enzyme showed a specific activity as high as 1,000 U/mg and had optimum activity at pH 11.5 and $50^{\circ}C$. It was composed of a single polypeptide chain with a molecular mass of 42 kDa deduced from SDS-PAGE, and its isoelectric point was around pH 6.0. It could efficiently depolymerize polygalacturonate and pectin. Characterization of product formation revealed unsaturated digalacturonate and trigalacturonate as the main products. The pectate lyase gene (pelA) contained an open reading frame (ORF) of 1,089 bp, encoding a 36-amino acids signal peptide and a mature protein of 326 amino acids with a calculated molecular mass of 35.943 Da. The deduced amino acid sequence from the pelA ORF exhibited significant homology to those of known pectate lyases in polysaccharide lyase family 1. Some conserved active-site amino acids were found in the deduced amino acid sequence of Bsp165PelA. $Ca^{2+}$ was not required for activity on pectic substrates.

• Korean Journal Plant Pathology
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• v.14 no.2
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• pp.125-129
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• 1998

Phytopathogenic bacteria causing soft-rot many vegetables; extracellular enzymes produced by them, pectate lyase(Pel) is important pathogenicity facotrs which cause tissue maceration and cell death. Ten of seventeen plant pathogenic bacteria showed weak Pel activity, four of them showed low Pel activity and Erwinia acrotovora subsp. carotovora, E. chrysanthemi, Pseudomonas marginalis and Xanthomonas campestris pv. campestris showed high Pel activity in the polygalacturonate yeast extract agar (PAY) plate. High Pel activity of the four bacteria species produced the highest Pel activity when pectin or polygalacturonic acid (PGA) was added to minimal salts (MS) medium. Pel activity of the four bacterial species was the highest at 2$0^{\circ}C$ among different temperature conditions. The rate and amount of maceration of potato tuber tissue were highest at 2$0^{\circ}C$ in E. carotovora subsp. carotovora, E. chrysanthemi and P. marginalis, while those were the highest at $25^{\circ}C$ in X. campestris pv. campetris.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1365-1370
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• 2009

Aspergillus kawachii extracellular pectinases were screened in liquid cultures with different carbon sources. The fungus grown on citrus pectin or lemon pomace produced at least one of these inducible pectinases: acidic polygalacturonase, pectin lyase, pectin methylesterase, $\alpha$-L-arabinofuranosidase, $\alpha$-1,5-endoarabinase, $\beta$-D-galactosidase/exogalactanase, and $\beta$-1,4-endogalactanase. The lemon-pomace filtrates also contained significant $\alpha$-L-rhamnosidase and $\beta$-D-fucosidase activities. Most of the screened pectinases were active at pH 2.0-2.5, indicating that the A. kawachii enzymes were acidophilic. Under the culture conditions employed we could not detect enzymatic degradation of soybean rhamnogalacturonan. The A. kawachii pectinase-production-related regulatory phenomena of induction-repression resemble those described for other Aspergillus sp.

• Korean Journal of Pharmacognosy
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• v.48 no.3
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• pp.195-201
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• 2017

To develop new therapy for prevention and treatment of hair loss is very important according to increase of the number of hair loss people. The aim of this study was to investigate the hair growth promoting effects of pectin lyase-modified red ginseng extract (GS-E3D). We examined antioxidant and anti-inflammatory effects, human hair dermal papilla cells (HHDPC) proliferation, and testoterone-induced $5{\alpha}$-reductase inhibitory effects. GS-E3D show not only 1,1-diphenyl-2-picryhydrazyl (DPPH) radical scavenging activity and xanthine oxidase inhibitory effects as an anti-oxidant property, but also lip-oxygenase and hyaluronidase inhibitory effects as an anti-inflammatory property. Human hair dermal papilla cells proliferation by GS-E3D was higher than those of minoxidil or finasteride, using the positive controls. Moreover, GS-E3D exhibited $5{\alpha}$-reductase inhibitory activities after stimulating by testoterone. The present results indicate that GS-E3D has a potential to be as an hair growth promoting agent for cosmetic materials.

• Korean Journal of Pharmacognosy
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• v.49 no.3
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• pp.246-254
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• 2018

Pectin lyase-modified red ginseng extract (GS-E3D) is a newly developed ginsenoside Rd-enriched ginseng extract. This study was designed to investigate the skin safety of GS-E3D. Single oral toxicity, single dermal toxicity, bovine corneal opacity and permeability (BCOP) assay, skin irritation test with $SkinEthic^{TM}$ human epidermis model, skin sensitization local lymph node assay, and human patch test, were examined. The oral and dermal $LD_{50}$ value of GS-E3D was over 2,000 mg/kg in rats. GS-E3D was identified as a non-irritant to skin in BCOP assay, human epidermis models, and patch test from the 32 human subjects. The skin sensitization potential of GS-E3D was less than 25% in local lymph node assay. These results indicate that GS-E3D can be used as a safe ingredient without adverse effects in various skin care products.

• The Korea Journal of Herbology
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• v.33 no.4
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• pp.1-7
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• 2018

Objectives : Diabetic nephropathy is one of the most significant chronic complications of diabetes. Advanced glycation end products (AGEs) have been implicated in the development of diabetic nephropathy. GS-E3D is an enzymatic modified red ginseng extract by pectin lyase and has an increased concentration of the ginsenoside Rd compared to an unmodified red ginseng extract. In this study, we evaluated the preventive effects of GS-E3D on renal dysfunction in the type 2 diabetic db/db mice. Methods : GS-E3D (100 or 250 mg/kg body weight per day) was given to db/db mice through oral gavage for 6 weeks. Body weight and blood glucose levels were examined. At the end of the experiment, albuminuria was measured. The renal tissues were collected for histological examination, and immunohistochemical staining was used to detect renal accumulation of AGEs and podocyte loss Results : In the db/db mice, severe hyperglycemia developed, and albuminuria was significantly increased. Diabetes induced markedly morphological alterations to the renal glomerular cells. AGE accumulations and podocyte loss were detected in renal glomeruli. No difference in blood glucose levels was noted between GS-E3D-treated and vehicletreated diabetic db/db mice. However, GS-E3D treatment significantly reduced albuminuria and AGE accumulations in diabetic mice. Moreover, the loss of podocytes was restored by GS-E3D treatment. Conclusions : GS-E3D might be beneficial for the treatment of diabetic nephropathy. The ability of GS-E3D on to attenuate albuminuria and podocyte dysfunction in the db/db mice may be mediated by the inhibition of AGE accumulation.

• Research in Plant Disease
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• v.18 no.3
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• pp.240-244
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• 2012

Burkholderia gladioli pv. alliicola CH1 showed typical soft rot symptoms at higher than $20^{\circ}C$ but very weak soft rot symptoms at temperature under $10^{\circ}C$. Among the nine agro-chemicals, oxolinic acid WP, streptomycin + copper hydroxide WP and streptomycin WP were found to be effective for the inhibition of the pathogen in vitro. The results of scanning electron microscopic investigation showed that onion bulbs was macerated by infection of B. gladioli pv. alliicola CH1. B. gladioli pv. alliicola CH1 was able to produce polygalacturonase but did not produce pectin lyase and carboxymethylcellulase. In analysis of the polygalacturonase activity of the isolated pectin-degradation enzymes from B. gladioli pv. alliicola CH1 total protein, three activity bands 45 kDa, 35 kDa, and 29 kDa were detected by the direct (or in-gel) activity staining on SDS-PAGE.