The Rumen Ecosystem : As a Fountain Source of Nobel Enzymes - Review -

Lee, S.S.,Shin, K.J.,Kim, W.Y.,Ha, J.K.,Han, In K. Asian Australasian Association of Animal Productio 1999 Animal Bioscience Vol.12 No.6

The rumen ecosystem is increasingly being recognized as a promising source of superior polysaccharide-degrading enzymes. They contain a wide array of novel enzymes at the levels of specific activities of 1,184, 1,069, 119, 390, 327 and $946{\mu}mol$ Reducing sugar release/min/mg protein for endoglucanase, xylanase, polygalactouronase, amylase, glucanase and arabinase, respectively. These enzymes are mainly located in the surface of rumen microbes. However, glycoside-degrading enzymes (e.g. glucosidase, fucosidase, xylosidase and arabinofuranosidase, etc.) are mainly located in the rumen fluid, when detected enzyme activities according to the ruminal compartments (e.g. enzymes in whole rumen contents, feed-associated enzymes, microbial cell-associated enzymes, and enzymes in the rumen fluid). Ruminal fungi are the primary contributors to high production of novel enzymes; the bacteria and protozoa also have important functions, but less central roles. The enzyme activities of bacteria, protozoa and fungi were detected 32.26, 19.21 and 47.60 mol glucose release/min/mL mediem for cellulose; 42.56, 14.96 and 64.93 mmol xylose release/min/mL medium after 48h incubation, respectively. The polysachharide-degrading enzyme activity of ruminal anaerobic fungi (e.g. Neocallimastix patriciarum and Piromyces communis, etc.) was much higher approximately 3~6 times than that of aerobic fungi (e.g. Tricoderma reesei, T. viridae and Aspergillus oryzae, etc.) used widely in industrial process. Therefore, the rumen ecosystem could be a growing source of novel enzymes having a tremendous potential for industrial applications.

A Genetic Circuit System Based on Quorum Sensing Signaling for Directed Evolution of Quorum-Quenching Enzymes

Kim, Jin-Hyun,Lee, Sang-Chul,Kyeong, Hyun-Ho,Kim , Hak-Sung WILEY-VCH Verlag 2010 Chembiochem Vol.11 No.12

<P>Quorum sensing is a cell–cell communication mechanism that is involved in the regulation of biological functions such as luminescence, virulence, and biofilm formation. Quorum-quenching enzymes, which interrupt quorum-sensing signaling through degradation of quorum-sensing molecules, have emerged as a new approach to controlling and preventing bacterial virulence and pathogenesis. In an effort to develop quorum-quenching enzymes with improved catalytic activities, a genetic circuit system based on acylhomoserine-lactone (AHL)-mediated quorum-sensing signaling was constructed. The genetic circuit system was composed of lux-R, lux-I promoter, β-lactamase, and β-lactamase inhibitor, and designed to confer antibiotic resistance on host cells expressing an AHL-degrading enzyme, thereby enabling rapid screening of quorum-quenching enzymes. To demonstrate the utility of the genetic circuit system, we attempted the directed evolution of the AHL hydrolase from Bacillus sp. The genetic circuit system was shown to be effective in screening of quorum-quenching enzymes with high catalytic efficiency. From these results it is expected that the genetic circuit system can be widely used for the isolation and directed evolution of quorum-quenching enzymes with greater potential.</P> <B>Graphic Abstract</B> <P>Quorum quenching: A genetic circuit based on AHL-mediated quorum sensing signaling has been constructed that is designed to confer antibiotic resistance to host cells expressing an AHL-degrading enzyme, thereby enabling rapid screening of quorum-quenching enzymes. The genetic circuit system was shown to be effective in screening of quorum-quenching enzymes with high catalytic efficiency. <img src='wiley_img_2010/14394227-2010-11-12-CBIC201000033-content.gif' alt='wiley_img_2010/14394227-2010-11-12-CBIC201000033-content'> </P>

Influence of Supplemental Enzymes, Yeast Culture and Effective Micro-organism Culture on Gut Micro-flora and Nutrient Digestion at Different Parts of the Rabbit Digestive Tract

Samarasinghe, K.,Shanmuganathan, T.,Silva, K.F.S.T.,Wenk, C. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.6

An experiment of 10 weeks duration was carried out to study the influence of supplemental effective microorganism (EM) culture, yeast culture and enzymes on nutrient digestibility and gut microflora in rabbit gastrointestinal (GI) tract. Twenty four eight to nine weeks old, New Zealand White rabbits were allotted to four dietary treatments; a basal (control) feed, basal feed supplemented with either EM (1%), yeast culture or enzymes (400 ppm). Nutrient flow in digesta and their digestibility at ileum, caecum, colon and in the total tract as well as gut microflora distribution were studied. Feed dry matter was diluted from 92% to about 14% up to the ileum and about 95% of this water was reabsorbed by the colonic rectal segment followed by caecum (25%). EM and yeast improved protein digestibility at a lower rate than enzymes. Ileal, caecal, colonic and total tract digestibility of crude protein with enzymes were higher by 10.8, 9.4, 11.3 and 10.7%, respectively, as compared to the control. Yeast and enzymes increased crude fiber digestibility at ileum, caecum, colon and in the total tract by 8.5, 9.6, 9.0 and 8.3%, respectively, while EM improved them at a lower rate. Irrespective of treatments, total tract digestibility of crude protein (0.698-0.773) and fiber (0.169-0.183) were greater (p<0.05) than the ileal digestibility. Even though a post-caecal protein digestibility was observed, fiber digestion seemed to be completed in the caecum especially with yeast and enzymes. High precaecal digestibility of crude fiber (97%) and protein (95%) were observed even without additives probably due to caecotrophy. EM and yeast culture promoted the growth of lactic acid bacteria especially in the caecum but they did not influence gut yeast and mould. Present findings reveal that even though rabbits digest nutrients efficiently through hind gut fermentation, they can be further enhanced by EM, yeast and enzymes. Of the three additives tested, enzymes found to be the best.

Sulfakinin inhibits activity of digestive enzymes in the brown planthopper, Nilaparvata lugens

Guo Di,Zhang Su,Zhang Yi-Jie,Ma Jun-Yu,Gao Cong-Fen,Wu Shun-Fan 한국응용곤충학회 2020 Journal of Asia-Pacific Entomology Vol.23 No.4

In animals, feeding can regulate release of digestive enzymes. Digestive enzymes are produced and released in response to specific ratios of nutrients, so the quality and quantity of food ingested are important factors in the secretion and activity of digestive enzymes. In general, the enzyme activity and secretion in the fed insects are relatively higher than that in the unfed insects. Neuropeptides and peptide hormones are important regulators of enzyme activity. In several insects, the neuropeptide sulfakinin (SK) is known to be a regulator of feeding and digestion similar to cholecystokinin in mammals. However, the roles of diet and SK in regulation of activity of digestive enzymes in the important pest insect, the brown planthopper (Nilaparvata lugens), are unknown. In this study, we identified six genes encoding different digestive enzymes and cloned three of these. We found that enzymatic activity and transcriptional levels of digestive enzymatic activity genes were upregulated by refeeding animals for 5 h after 24 h starvation. Furthermore, injection of N. lugens SK reduces digestive enzyme activity and leads to a downregulation of digestive enzyme gene transcripts. This study provides new views into the action of diet and SK in regulation of digestive enzymes in (hemimetabolous) insects. Taken together with the roles of SK in inducing satiety, our data strongly suggest that SK signaling is important in regulation of food ingestion and processing.

Single enzyme nanoparticles armored by a thin silicate network: Single enzyme caged nanoparticles

Hong, Sung-Gil,Kim, Byoung Chan,Na, Hyon Bin,Lee, Jinwoo,Youn, Jongkyu,Chung, Seung-Wook,Lee, Chang-Won,Lee, Byoungsoo,Kim, Han Sol,Hsiao, Erik,Kim, Seong H.,Kim, Byung-Gee,Park, Hyun Gyu,Chang, Ho Na Elsevier 2017 Chemical engineering journal Vol.322 No.-

<P><B>Abstract</B></P> <P>For the encapsulation of biomolecules in inorganic materials, we have developed a unique enzyme-silicate conjugate material that consists of a self-assembled molecularly thin silicate layer on the surface of each individual enzyme molecule. The enzyme-silicate conjugate materials, called single enzyme caged nanoparticles (SECNs), were synthesized via the silica polymerization on the surface of enzyme molecule after solubilizing each enzyme molecule in hexane by using a tiny amount of surfactant, called “ion-pairing”. SECNs possess near native enzyme activity in aqueous media with minimal substrate diffusional limitations, and are highly stable under the protection of silicate network cage. Due to their nearly molecular size, SECNs can also be adsorbed into mesoporous silica materials to yield robust and easily-recyclable enzymatic systems that can be used in a number of potential biocatalytic applications such as diagnostics, biosensors, biotransformations, biofuel production, bioremediation and CO<SUB>2</SUB> capture.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Protocol of single enzyme caged nanoparticles (SECNs) has been developed. </LI> <LI> SECNs have ultra-thin silicate network on the surface of individual enzyme molecule. </LI> <LI> SECNs minimize substrate diffusional limitation, and inhibit the enzyme denaturation. </LI> <LI> SECNs can be immobilized into mesoporous silica for recyclable enzymatic systems. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Prospects of reusable endogenous hydrolyzing enzymes in bioethanol production by simultaneous saccharification and fermentation

Waleed Ahmad Khattak,박중곤,마잘울이슬람 한국화학공학회 2012 Korean Journal of Chemical Engineering Vol.29 No.11

This study was conducted to evaluate the presence, origination and classification of various hydrolyzing enzymes from malt and their specified hydrolyzing effects on various substrates for bioethanol production and to link these characteristics with the future prospects of bioethanol production. These enzymes are categorized as cell wall,starch, protein, lipid, polyphenol and thiol hydrolyzing enzymes based on their substrate specificity. Waste from beer fermentation broth (WBFB) has been evaluated as a rich source of malt derived hydrolyzing enzymes with significant self potential for bioethanol production. However, yeast cells cannot survive at the high temperature required for the saccharification activities of hydrolyzing enzymes during simultaneous saccharification and fermentation (SSF). This dilemma might be resolved by bioethanol production at elevated temperatures via cell-free fermentation systems in the presence of malt hydrolyzing enzymes. Moreover, emerging technologies such as genetic engineering in biomass and biotransformation in cell-free enzymatic systems will likely hasten bioethanol production in the near future. The present study adds new dimensions to eco-friendly bioethanol production from renewable and waste energy resources based on the specific hydrolyzing activities of malt enzymes.

Supplemental Enzymes, Yeast Culture and Effective Micro-organism Cultureto Enhance the Performance of Rabbits Fed Diets Containing High Levels of Rice Bran

Shanmuganathan, T.,Samarasinghe, K.,Wenk, C. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.5

An experiment was carried out to study the effects of exogenous enzymes (cellulases and proteases), yeast culture and effective micro-organism (EM) culture on feed digestibility and the performance of rabbits fed rice bran rich diets over a period of ten weeks. Twenty four, 8 to 9 weeks old male and female New Zealand White rabbits were allotted to 4 dietary treatments; a basal (control) feed containing 43% rice bran, basal feed supplemented with either enzymes, yeast culture or EM. Individual feed intake, body weight gain, nutrient digestibility, carcass characteristics and feed cost were studied. Sex of the rabbits had no significant (p<0.05) influence on the parameters studied. The control group showed the lowest daily feed intake (104.8 g), body weight gain (12.8 g) and the highest feed/gain ratio (8.20 g/g). The highest daily feed intake (114.3 g), body weight gain (20.42 g) and the lowest feed/gain ratio (5.60) were observed with enzymes. Compared to the control, yeast significantly (p<0.05) improved the feed intake, body weight gain and feed/gain ratio by 4.9, 34.4 and 22.0%, respectively, while EM improved (p<0.05) them by 4.0, 32.6 and 21.6%, respectively. All the additives improved (p<0.05) the digestibility of dry matter, crude protein, crude fiber and energy by 4.9-8.7, 3.6-10.7, 5.9-8.3 and 4.3-6.4%, respectively. Higher weights of pancreas (by 38.5-56.4%) and caecum (by 13.1-26.8%, compared to the control) were recorded with all additives but liver weight was increased only by yeast (24.5%) and enzymes (26.7%). Significantly (p<0.05) higher carcass recovery percentages were observed with enzymes (60.55), yeast (60.47) and EM (56.60) as compared to the control (48.52). Enzymes, yeast and EM reduced (p<0.05) the feed cost per kg live weight by 23.8, 15.9 and 15.5%, respectively. Results revealed that enzymes, yeast culture and EM can be used to improve the feeding value of agro-industrial by-products for rabbits in Sri Lanka and thereby to reduce the feed cost. Under the present feeding system, enzyme supplement was the best.

Binding Pattern Elucidation of NNK and NNAL Cigarette Smoke Carcinogens with NER Pathway Enzymes: an Onco-Informatics Study

Jamal, Qazi Mohammad Sajid,Dhasmana, Anupam,Lohani, Mohtashim,Firdaus, Sumbul,Ansari, Md Yousuf,Sahoo, Ganesh Chandra,Haque, Shafiul Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.13

Cigarette smoke derivatives like NNK (4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone) and NNAL (4-(methylnitrosamino)-1-(3-pyridyl)-1-butan-1-ol) are well-known carcinogens. We analyzed the interaction of enzymes involved in the NER (nucleotide excision repair) pathway with ligands (NNK and NNAL). Binding was characterized for the enzymes sharing equivalent or better interaction as compared to +Ve control. The highest obtained docking energy between NNK and enzymes RAD23A, CCNH, CDK7, and CETN2 were -7.13 kcal/mol, -7.27 kcal/mol, -8.05 kcal/mol and -7.58 kcal/mol respectively. Similarly the highest obtained docking energy between NNAL and enzymes RAD23A, CCNH, CDK7, and CETN2 were -7.46 kcal/mol, -7.94 kcal/mol, -7.83 kcal/mol and -7.67 kcal/mol respectively. In order to find out the effect of NNK and NNAL on enzymes involved in the NER pathway applying protein-protein interaction and protein-complex (i.e. enzymes docked with NNK/NNAL) interaction analysis. It was found that carcinogens are well capable to reduce the normal functioning of genes like RAD23A (HR23A), CCNH, CDK7 and CETN2. In silico analysis indicated loss of functions of these genes and their corresponding enzymes, which possibly might be a cause for alteration of DNA repair pathways leading to damage buildup and finally contributing to cancer formation.

Assessment of testicular steroidogenic enzymes expression in experimental animal model following withdrawal of nandrolone decanoate

( Taesun Min ),( Adhimoolam Karthikeyan ),( Ki-ho Lee ) 한국축산학회 2021 한국축산학회지 Vol.63 No.6

Anabolic steroids are frequently used to increase the growth rate of meat-producing animals. Exposure to an anabolic-androgenic steroid, nandrolone decanoate (ND), is associated with expressional reduction of testicular steroidogenic enzymes. However, the effect of withdrawal of ND exposure on the expression of these testicular molecules has not been thoroughly explored. The current research investigated expression changes of testicular steroidogenic enzymes in rats at several recovery periods (2, 6, and 12 weeks) after the stop of ND treatment with different doses (2 and 10 mg/kg body weight) for 12 weeks. Body and testis weights were recorded, and transcript levels of molecules were determined by quantitative real-time polymerase chain reaction (PCR). The immunohistochemistry was used to examine the changes of immuno-intensities of molecules. At 6 and 12 weeks of the recovery period, the 10 mg/kg ND-treated rats were lighter than other experimental groups. The interstitial compartment vanished by ND treatment filled up as the recovery period became longer. The expression of steroidogenic acute regulatory protein was returned to the control level at 12 weeks of the recovery period. Expression levels of cytochrome P450 side-chain cleavage and 17a-hydroxylase were increased in 2 mg/kg ND-treated group at 6 weeks of the recovery period, and transcript levels of these molecules in 2 and 10 mg/kg ND-treated groups at 12 weeks of the recovery period were significantly lower than the control. Expression levels of 3β-hydroxysteroid dehydrogenase (HSD) type I and 17β-HSD type 3 in 2 mg/kg ND-treated group were comparable with those of control at 12 weeks of the recovery period, but not in 10 mg/kg ND-treated group. Expression of cytochrome P450 aromatase (Cyp19) was reverted to the control level at 2 weeks of the recovery period. Except for Cyp19, there was a visible increase of immuno-staining intensity of other testicular steroidogenic enzymes in the Leydig cells as the recovery period progressed. This research has demonstrated that the cease of ND administration could restore the expression of testicular steroidogenic enzymes close to the normal level. Nevertheless, a relatively long recovery period, compared to the ND-exposure period would be required to retrieve normal expression levels of testicular steroidogenic enzymes.

효소 농도별 막걸리의 쓴맛 감소 차이 비교

허좌영(Joa-Young Her),손은심(Eun-Shim Son),정철(Chul Cheong) 한국산학기술학회 2021 한국산학기술학회논문지 Vol.22 No.9

본 연구에서는 발효제를 달리하고 혼합효소 농도별로 처리한 후 발효시킨 막걸리의 쓴맛 차이를 비교하고자 하였다. 측정한 알코올은 모두 18~20% 정도로, 발효제와 혼합효소 처리와는 큰 관련이 없는 것으로 나타났다. pH 변화는 누룩과 입국 모두 4~4.3으로 차이가 없었다. 누룩과 입국의 총산도는 누룩의 경우 혼합효소를 처리하지 않은 시료에서 0.480으로 낮았으며. 다른 시료에서는 특별한 변화가 없었다. 유기산 총량은 혼합효소 각각의 농도에 대해서 누룩의 경우 입국보다 3배 정도 높았으며, 각각의 발효제에서 혼합효소의 농도 360ppm에서 유기산 함량이 가장 많이 증가한 것으로 나타났다. 향기성분에서 고급 알코올의 경우에는 누룩과 혼합효소 180ppm을 투입한 막걸리에서 유의적으로 가장 높은 농도를 보인 반면, 입국에서는 혼합효소 3600ppm을 투입한 입국 막걸리에서 유의적으로 가장 높은 농도를 보였다. 쓴맛 강도의 변화는 누룩과 입국 모두에게서 농도가 증가할수록 감소하였으며, 색, 향, 맛의 기호도 검사시 누룩과 입국 모두 혼합효소 360ppm 첨가시 가장 높은 점수를 받았다. 따라서 본 연구결과 입국을 사용하며 혼합효소의 농도 360ppm으로 막걸리를 제조하는 것이 소비자의 요구에 부합되리라 본다. This study compared and examined the difference in bitter taste of makgeolli fermented after treatment with different fermenters and varying concentrations of mixed enzymes. All measured alcohols were in the range 18 to 20%, and no significant relationship was observed between the different treatments with fermenters and mixed enzymes. The pH range remained unchanged (between 4 and 4.3) in both Nuruk and Koji. The total acidity of Nuruk and Koji was determined to be 0.480 in the samples not treated with mixed enzymes, with no particular change observed in the other samples. For each concentration of the mixed enzymes, the total amount of organic acid was 3 times higher when treated with Koji than with Nuruk, with maximum organic acid content obtained at 360 ppm concentration of the mixed enzymes in each fermenting agent. Determination of high-quality alcohol revealed significantly highest levels in makgeolli containing 180 ppm Nuruk and mixed enzymes. The change in bitter taste intensity decreased with increasing concentration in both Nuruk and Koji. Highest scores for color, aroma, and taste preferences in both Nuruk and Koji were obtained with the addition of 360 ppm mixed enzymes. Taken together, the results of this study indicate that fermentation of makgeolli using 360 ppm concentration of mixed enzymes and Koji will yield a product most acceptable to consumers.