Methods and compositions for improving plant traits

Inventors

Temme, Karsten • Tamsir, Alvin • BLOCH, Sarah • CLARK, Rosemary • TUNG, Emily

Assignees

Pivot Bio Inc

Abstract

Disclosed herein are methods of increasing nitrogen fixation in a non-leguminous plant. The methods can comprise exposing the plant to a plurality of bacteria. Each member of the plurality comprises one or more genetic variations introduced into one or more genes or non-coding polynucleotides of the bacteria's nitrogen fixation or assimilation genetic regulatory network, such that the bacteria are capable of fixing atmospheric nitrogen in the presence of exogenous nitrogen. The bacteria are not intergeneric microorganisms. Additionally, the bacteria, in planta, produce 1% or more of the fixed nitrogen in the plant.

Core Innovation

The disclosure describes a composition and related plant seed use for increasing nitrogen fixation activity in non-leguminous plants. The approach uses an engineered diazotroph comprising at least one genetic variation introduced in a nitrogen fixation genetic regulatory network, and the engineered diazotroph is configured to increase expression or activity of nifH and nifA, while decreasing expression or activity of nifL.

The genetic variation is described as genetic material that originates from the same genus as the engineered diazotroph. The engineered diazotroph has increased nitrogen fixation activity as compared to an unmodified organism of the same species as the engineered diazotroph, including in the presence of exogenous nitrogen or fertilizer conditions and thresholds for fixed nitrogen in planta.

The disclosure further provides embodiments in which genetic variations target regulatory and shutdown pathways within nitrogen fixation and nitrogen assimilation, including modifications associated with ntrB/ntrC, glnB/glnK/glnD, amtB, glnA/glnB, glutamine synthetase, glutaminase, and draT. The bacterial populations are described as non-intergeneric and intrageneric, including engineered diazotrophs such as Enterobacter and Rahnella, delivered as seed-coated or formulated bacterial populations.

Claims Coverage

Independent claim 1 covers an engineered diazotroph-based composition and a plant seed, with core inventive features comprising targeted genetic variations in a nitrogen fixation genetic regulatory network that increase nifH and nifA while decreasing nifL, and that originate from the same genus as the engineered diazotroph. Based on the provided claim text, only one independent claim is explicitly identified (clm-00001).

The claim coverage provided centers on an engineered diazotroph engineered in a nitrogen fixation genetic regulatory network to upregulate nifH and nifA and downregulate nifL, using genetic material originating from the same genus, resulting in increased nitrogen fixation activity versus an unmodified same-species organism, in combination with a plant seed.

Stated Advantages

Documented Applications

No documented applications found