IP Library › Granted Patent US 12,448,632
Granted Patent B2
US 12,448,632 · App. 17/555,350 · Granted Oct 21, 2025

Guanidine degradation enzyme and methods of use

Inventors: Jianping Yu (Golden, CO); Bo Wang (Nashville, TN)
Assignees: Alliance for Sustainable Energy, LLC; Vanderbilt University
C12P7/065C12N1/205C12N15/52C12R2001/01
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Quick Facts
Patent No.
US 12,448,632
App. No.
17/555,350
Granted
Oct 21, 2025
Kind
B2
Abstract

Presented herein are Synechococcus strains engineered to express the bacterial ethylene-forming enzyme (EFE) that exhibit unstable ethylene production due to toxicity and genomic instability induced by accumulation of the EFE-byproduct guanidine. Co-expression of EFE and Sll1077 significantly enhanced genomic stability and enabled the resulting Synechococcus strain GD-EFE7942 to achieve sustained high-level ethylene production. The engineered strains and methods disclosed herein are useful for guanidine degradation pathways and for ethylene bioproduction in cyanobacteria.

Claims (7)

1. A non-naturally occurring Synechocystis or Synechococcus cyanobacterial strain engineered to express a heterologous bacterial ethylene-forming enzyme (EFE) and a guanidine degradation enzyme.

2. The non-naturally occurring cyanobacterial strain of claim 1 wherein the guanidine degradation enzyme is encoded by sll1077.

3. The non-naturally occurring cyanobacterial strain of claim 1 comprising improved cell growth in a solution containing guanidine compared to a naturally occurring cyanobacterial strain.

4. The non-naturally occurring cyanobacterial strain of claim 1 wherein the cyanobacterial strain is selected from the group consisting of Synechocystis PB816H, Synechocystis PB817H and Synechococcus elongatus GD.

5. The non-naturally occurring cyanobacterial strain of claim 1 wherein the strain is capable of ethylene production.

6. The non-naturally occurring cyanobacterial strain of claim 1 wherein the strain is capable of guanidine degradation.

7. A method for guanidine degradation comprising the step of exposing the non-naturally occurring cyanobacterial strain of claim 1 to a solution containing guanidine.

Assignments (5)
CHANGE OF NAME Recorded Dec 16, 2025
From: ALLIANCE FOR SUSTAINABLE ENERGY, LLC
To: ALLIANCE FOR ENERGY INNOVATION, LLC
Reel/Frame 073993/0276 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 8, 2025
From: ALLIANCE FOR SUSTAINABLE ENERGY, LLC
To: VANDERBILT UNIVERSITY
Reel/Frame 070770/0172 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 14, 2024
From: WANG, BO
To: ALLIANCE FOR SUSTAINABLE ENERGY, LLC
Reel/Frame 068279/0732 →
CONFIRMATORY LICENSE Recorded May 18, 2022
From: NATIONAL RENEWABLE ENERGY LABORATORY
To: UNITED STATES DEPARTMENT OF ENERGY
Reel/Frame 059948/0030 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 3, 2022
From: YU, JIANPING
To: ALLIANCE FOR SUSTAINABLE ENERGY, LLC
Reel/Frame 058527/0025 →
Continuity (2)
Provisional Application 63126828 · Dec 17, 2020
Related Publication 20220204998A1 · Jun 30, 2022
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