• 我要登录|
  • 免费注册
    |
  • 我的丁香通
    • 企业机构:
    • 成为企业机构
    • 个人用户:
    • 个人中心
  • 移动端
    移动端
丁香通 logo丁香实验_LOGO
搜实验

    大家都在搜

      大家都在搜

        0 人通过求购买到了急需的产品
        免费发布求购
        发布求购
        点赞
        收藏
        wx-share
        分享

        Isolation and Characterization of an Unknown Restriction Endonuclease

        互联网

        577
        Currently, there are approx 3000 restriction endonucleases known, recognizing 235 different sequences (1 ). Although primarily found in bacteria, they also exist in archaea, viruses, and eukaryotes. An estimated 25% of bacteria examined contain at least one restriction endonuclease (2 ), and therefore the probability of encountering new ones is relatively high. Indeed, many new enzymes have been “discovered” in contaminated bacterial cultures. The presence of three restriction activities in a single organism is not unusual. Neisseria strains appear to be particularly rich in restriction endonucleases and their corresponding methyltransferases. As many as seven different endonucleases from a single strain have been idenitified through cloning (3 ). The first enzyme discovered which recognizes a unique sequence, although it may not be commercially available or commonly known, is designated the prototype. Although few new prototypes have been discovered recently, two potential four-base palindromes and seven potential six-base palindromes are not cleaved by any known restriction endonucleases. Most databases are arranged alphabetically by prototype, with isoschizomers listed under the prototype heading. A database of all known endonucleases, maintained by Dr. Richard J. Roberts, is available at http://www.neb.com/rebase . A number of formats are available, and references are provided. Detailed information on restriction endonuclease biology, classification, structure, specificity, and catalytic mechanism is provided elsewhere in this book (see Chapters 19 , 27 , and 29 ).
        ad image
        提问
        扫一扫
        丁香实验小程序二维码
        实验小助手
        丁香实验公众号二维码
        扫码领资料
        反馈
        TOP
        打开小程序