Enzyme amplification by using free enzyme to release enzyme from an immobilized enzyme material

• US 5,190,864 A
• Filed: 04/30/1990
• Issued: 03/02/1993
• Est. Priority Date: 04/15/1986
• Status: Expired due to Fees

• Current Assignee: Northeastern University
• Original Assignee: Northeastern University
• Inventors: Ehrat, Markus, Cecchini, Douglas J., Giese, Roger W.
• Primary Examiner(s): Naff, David M.
• Application Number:
  US07/516,321
• Time in Patent Office: 1,037 Days
• Field of Search: 435/3, 435/4, 435/7.9, 435/7.92, 435/41, 435/174, 435/176, 435/177, 435/178, 435/181, 435/183, 435/188
• US Class Current: 435/41
• CPC Class Codes: C12N 9/22 Ribonucleases RNAses, DNAses catalytic nucleic acids C12N15/113
• CPC Class Codes: C12Q 1/00 Measuring or testing processes involving enzymes, nucleic acids or microorganisms measuring or testing apparatus with condition measuring or sensing means, e.g. colony counters, C12M1/34; Compositions therefor; Processes of preparing such compositions
• CPC Class Codes: C12Q 1/68 involving nucleic acids

Abstract

A method for amplifying enzyme activity is disclosed. Enzyme amplification is achieved by covalently bonding enzyme to a supporting material via a molecular chain which is a substrate for the enzyme, then introducing a small amount of enzyme in the free state to this system, causing release of a large amount of bound enzyme. In an alternative embodiment, complementary enzymatically inactive fragments of an active enzyme, which fragments can recombine to form active enzyme, are covalently attached to separate support materials by a molecular chain material which is a substrate for the active enzyme, and these two fragment-supported conjugates are connected in series. Upon application of free enzyme or free complementary enzyme to one of these fragment-support conjugates, followed by application of the resulting product mixture to the second fragment-support conjugate, a large amount of free enzyme is ultimately produced. In a second alternative embodiment, two different active enzymes are each attached to separate supporting materials by different leashes, in which the leash for the first enzyme only is cleaved in the system by the second enzyme, and the leash for the second enzyme only is cleaved in the system by the first enzyme. These two materials are connected in series, and upon application of the second enzyme to the first enzyme-support conjugate, followed by application of the released first enzyme to the second enzyme-support conjugate material, ultimately a large amount of released active second enzyme is produced. Also disclosed are molecular conjugates of enzyme material on supports, required for the enzyme amplification.

Claims

1. A method for amplifying enzymatic activity, comprising:

providing a support-leash-enzyme conjugate wherein the support is a solid, the leash comprises molecular chain which is cleavable by the enzyme in the free state, the leash is attached to the support and to the enzyme by covalent bonds, and the conjugate has a plurality of -leash-enzyme units connected to the support;

said conjugate being structured such that the bound enzyme of a given -leash-enzyme unit is unable to cleave the leash portion of that unit;

adding to said conjugate a first amount of said enzyme in the free state, to produce a mixture of free enzyme and support-leash-enzyme conjugate;

incubating said mixture a predetermined period of time, to cause enzyme from said conjugate to be released into the free state; and

recovering said enzyme in the free state from said conjugate in a second amount greater than said first amount of enzyme.

2. The method of claim 1 wherein said conjugate is structured such that the leash of each of a plurality of -leash-enzyme units is joined to the support in at least two positions, to prevent enzyme of such -leash-enzyme units from cleaving the associated leashes.

3. The method of claim 1 wherein the leash material of said conjugate further comprises a spacer substance adjacent to the bound enzyme, said spacer being a material which is not cleavable by the enzyme, and preventing bound enzyme of -leash-enzyme units from reaching and cleaving the associated leashes.

4. The method of claim 1 further comprising the steps of:

providing at least one additional support-leash-enzyme conjugate in series with said support-leash-enzyme conjugate;

adding to each additional support-leash-enzyme conjugate the recovered enzyme from the preceding support-leash-enzyme conjugate to produce an additional mixture of enzyme and conjugate; and

repeating said incubating and recovering steps for each additional support-leash-enzyme conjugate.

5. A molecular conjugate composition having the generalized formula

View Dependent Claims (6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)

6. The composition of claim 5 wherein the support material is agarose, silica, cellulose, Sepharose, Trisacryl, glass, nylon, polymethacrylate, Immobilon Membrane, polyacrylamide, polyamide or gelatin.

7. The composition of claim 5 wherein the leash comprises polycytidylic acid and the enzyme is ribonuclease or ribonuclease S.

8. The composition of claim 5 wherein the leash comprises polycytidylic acid and the enzyme is ribonuclease A.

9. The composition of claim 5 wherein the leash comprises deoxyribonucleic acid and the enzyme is Staphlococcal nuclease.

10. The composition of claim 5 wherein the leash comprises thymidine diphosphate and the enzyme is Staphlococcal nuclease.

11. The composition of claim 5 wherein the leash comprises deoxyribonucleic acid and the enzyme is restriction endonuclease Tag-I.

12. The composition of claim 5 wherein the leash comprises deoxyribonucleic acid and the enzyme is restriction endonuclease Hinf I.

13. The composition of claim 5 wherein the leash comprises galactan and the enzyme is β

-galactosidase.

14. The composition of claim 5 wherein the leash comprises dextrin and the enzyme is amylase.

15. The composition of claim 5 wherein the leash comprises Micrococcus Lysocleikticus and the enzyme is lysozyme.

16. The composition of claim 5 wherein the leash comprises cellulose and the enzyme is a cellulase.

17. The composition of claim 5 wherein the leash comprises polypeptide and the enzyme is a sulfhydryl protease.

18. The composition of claim 5 wherein the leash comprises polypeptide and the enzyme is a protease.

19. A molecular conjugate composition having the generalized formula

View Dependent Claims (20, 21, 22, 23, 24)

20. The composition of claim 19 wherein the support is agarose, silica, cellulose, Sepharose, Trisacryl, glass, nylon, polymethacrylate, Immobilon Membrane, polyacrylamide, polyamide or gelatin.

21. The composition of claim 19 wherein the leash comprises polycytidylic acid and the enzyme fragment is the S-protein of ribonuclease S.

22. The composition of claim 19 wherein the leash comprises polycytidylic acid and the enzyme fragment is the S-peptide of ribonuclease S.

23. The composition of claim 19 wherein the leash comprises deoxyribonucleic acid and the enzyme fragment is Staphylococcal Nuclease (1-126).

24. The composition of claim 19 wherein the leash comprises deoxyribonucleic acid and the enzyme fragment is Staphylococcal Nuclease (99-149).