Single point mutations in various domains of a plant plasma membrane H(+)-ATPase expressed in Saccharomyces cerevisiae increase H(+)-pumping and permit yeast growth at low pH.

A eukaryotic formate dehydrogenase (EC 1.2.1.2, FDH) with its substrate specificity changed from NAD+ to NADP+ has been constructed by introducing two single-point mutations, Asp196→Ala (D196A) and Tyr197→Arg (Y197R). The mutagenesis was based on the results of homology modelling of a NAD+-specific FDH from Saccharomyces cerevisiae (SceFDH) using the Pseudomonas sp.101 FDH (PseFDH) crystal structure as a template. The resulting model structure suggested that Asp196 and Tyr197 mediate the absolute coenzyme specificity of SceFDH for NAD+.

Download Full-text

Cupin Variants as Macromolecular Ligand Library for Stereoselective Michael Addition of Nitroalkanes

10.26434/chemrxiv.11481834.v1 ◽

2019 ◽

Author(s):

Nobutaka Fujieda ◽

Miho Yuasa ◽

Yosuke Nishikawa ◽

Genji Kurisu ◽

Shinobu Itoh ◽

...

Keyword(s):

Michael Addition ◽

In Silico ◽

Addition Reaction ◽

Single Point ◽

Point Mutations ◽

Unsaturated Ketone ◽

Michael Addition Reaction ◽

Beta Barrel ◽

Cupin Superfamily ◽

Single Point Mutations

Cupin superfamily proteins (TM1459) work as a macromolecular ligand framework with a double-stranded beta-barrel structure ligating to a Cu ion through histidine side chains. Variegating the first coordination sphere of TM1459 revealed that H52A and H54A/H58A mutants effectively catalyzed the diastereo- and enantio-selective Michael addition reaction of nitroalkanes to an α,β-unsaturated ketone. Moreover, in silico substrate docking signified C106N and F104W single-point mutations, which inverted the diastereoselectivity of H52A and further improved the stereoselectivity of H54A/H58A, respectively.

Download Full-text

Single-Point Mutations in Qβ Virus-like Particles Change Binding to Cells

Biomacromolecules ◽

10.1021/acs.biomac.1c00443 ◽

2021 ◽

Author(s):

Marisa L. Martino ◽

Stephen N. Crooke ◽

Marianne Manchester ◽

M.G. Finn

Keyword(s):

Single Point ◽

Point Mutations ◽

Virus Like Particles ◽

Single Point Mutations

Download Full-text

MinD directly interacting with FtsZ at the H10 helix suggests a model for robust activation of MinC to destabilize FtsZ polymers

Biochemical Journal ◽

10.1042/bcj20170357 ◽

2017 ◽

Vol 474 (18) ◽

pp. 3189-3205 ◽

Cited By ~ 6

Author(s):

Ashoka Chary Taviti ◽

Tushar Kant Beuria

Keyword(s):

Cell Division ◽

Single Point ◽

Point Mutations ◽

Direct Interaction ◽

Ring Formation ◽

Z Ring ◽

Single Point Mutations ◽

Biochemical Analyses ◽

Ftsz Assembly ◽

The Mind

Cell division in bacteria is a highly controlled and regulated process. FtsZ, a bacterial cytoskeletal protein, forms a ring-like structure known as the Z-ring and recruits more than a dozen other cell division proteins. The Min system oscillates between the poles and inhibits the Z-ring formation at the poles by perturbing FtsZ assembly. This leads to an increase in the FtsZ concentration at the mid-cell and helps in Z-ring positioning. MinC, the effector protein, interferes with Z-ring formation through two different mechanisms mediated by its two domains with the help of MinD. However, the mechanism by which MinD triggers MinC activity is not yet known. We showed that MinD directly interacts with FtsZ with an affinity stronger than the reported MinC–FtsZ interaction. We determined the MinD-binding site of FtsZ using computational, mutational and biochemical analyses. Our study showed that MinD binds to the H10 helix of FtsZ. Single-point mutations at the charged residues in the H10 helix resulted in a decrease in the FtsZ affinity towards MinD. Based on our findings, we propose a novel model for MinCD–FtsZ interaction, where MinD through its direct interaction with FtsZ would trigger MinC activity to inhibit FtsZ functions.

Download Full-text