- Comparison of Two Methods for ...
- www.sscpc.cc的网站权重综合查询 爱站网
- 酶免疫电镜技术原理、材料和操作方法资讯
- 抗生素检定培养基8号_培养基
- 英国首席医疗官:抗生素耐药性是最大的危险抗生素耐药性,耐药菌...
- 抗酒石酸酸性磷酸酶(TRAP)检测试剂盒(PNP比色法)_价...
- A Method for Assaying Deubiqui...
- WAKO 购买须知|产品资讯
- 琼脂培养基c_琼脂培养基c【价格,厂家,图片,批发,采购】
- 咨询苏州社保卡在昆山地区的使用 寒山闻钟 苏州阳光便民 ...
- HEK293T Cell Line GE Dharmaco...
- 上皮抗原免疫组化试剂盒有限公司
- [09-28]头孢类药物一、二、三、四代特点及种类
- [08-04]吃抗生素药的副作用有哪些_
- [08-13]抗菌药物预防性应用的基本原则
- [07-21]葵花宝典:欲练此功必先自宫!_1_视频在线观看 56.com
- [07-24]孕产妇,哪些抗生素不能用?
- [09-28]什么抗生素不易产生耐药性?怎样吃药可减少耐药性?(高分送上...
- [08-08]剖宫产术后没有异常,常规用抗生素几天,谢谢_有问必答_
- [08-11]为什么要慎用抗生素_为什么要慎用抗生素_网易公开课
- [08-05]药理学的抗生素记忆口诀
Pectinase assay
Pectinasesareactuallyamixtureofenzymes,which,alongwithotherssuchascellulase,arewidelyusedinthefruitjuiceindustrywheretheyarewidelyusedtohelpextract,clarifyandmodifyfruitjuices.(Seethefootofthispageformoreinformation) Pectinsarelargepolysaccharidemolecules,madeup(mainly)ofchainsofseveralhundredgalacturonicacidresidues.Enzymesinthispectinasegroupincludepolygalacturonases,pectinmethylesteraseandpectinlyases.Thesepectinaseenzymesactindifferentwaysonthepectins,whicharefoundintheprimarycellwallsandinthemiddlelamella.PectinsarewellknownalsofortheirABIlitytoformgels. Pectinasesareproducedduringthenaturalripeningprocessofsomefruits,wheretogetherwithcellulases,theyhelptosoftentheircellwalls.TheseenzymesarealsosecretedbyplantpathogenssuchasthefungusMoniliniafructigenaandthesoft-rotbacteriumErwiniacarotovora,aspartoftheirstrategyforpenetratingtheplanthostcellwalls.Infact,theproductsofsuchenzymeassaults(oligosaccharins)actasasignalwhichinducesuninfectedcellstodefendthemselves. Theprincipleofthisassaydependsuponmeasuringtheamountofwateryjuicereleasedfromtinnedapplepuree(whichisveryrichinpectin)asaresultofpectinaseaction. Tinnedorbottledapplepuree(sauce)canbepurchasedforthisassay. Thedifferencesinthevolumeofjuicebetweenthetwotubesgivesameasureofthepectinaseactivityintheextract. Ifthisexperimentisbeingcarriedoutonalargescale,theinitialdrainagefromthefunnelscouldbecollectedintesttubes,andthenthevolumeofjuicecollectedismeasuredlater. Manyindustrialenzymeproductsaremixturesofdifferentenzymes.Thusa"pectinase"preparationmightcontainarangeofpectinasesandcellulases.Otherpreparationsmightcontainonlyasingletypeofenzyme,especiallyiftheenzymesareproducedbygenetically-modifiedstrainsorarehighlypurified. Whenplanningyourowninvestigations,itisthereforeveryimportanttostudythedatasheetsuppliedwitheachenzyme.Thiswillindicatewhethertheproductisamixtureorcontainsjustonetypeofenzyme. Thedatasheetalsoprovidesaroughguidetohowtheenzymemightbehave.Inpractice,however,enzymeactivityisaffectedbymanythings(e.g.pH,temperature,thepresenceofinhibitorsorcofactors)whichwillaffecttheresultsyouobtain.Inaddition,specimenactivitygraphsareoftenpreparedusingsimplesubstancesunderidealconditionsratherthanthecomplexsubstratesandsub-optimalconditionsthatmaybeencounteredinanindustrialorschoolcontext.
================ 蚂蚁淘在线 ================ 免责声明:本文仅代表作者个人观点,与本网无关。其创作性以及文中陈述文字和内容未经本站证实,对本文以及其中全部或者部分内容、文字的真实性、完整性、及时性本站不做任何保证或承诺,请读者仅作参考,并请自行核实相关内容 版权声明:未经蚂蚁淘在线授权不得转载、摘编或利用其他方式使用上述作品。已经经本网授权使用作品的,应该授权范围内使用,并注明“来源:蚂蚁淘在线”。违反上述声明者,本网将追究其相关法律责任。
Note:whenusingcommerciallypreparedenzymesinyourinvestigations...