B. Kacar

Molecular and structural innovations of the stator motor complex at the dawn of flagellar motility

This study classifies and characterizes MotAB stator complexes across bacterial phyla, identifying structural innovations linked to flagellar motility.

Evolutionary Dynamics of RuBisCO: Emergence of the Small Subunit and its Impact Through Time

The paper analyzes the evolutionary dynamics of RuBisCO, showing how the small subunit influenced the enzyme's conformational flexibility and response to atmospheric changes.

The Origins of ATP Dependence in Biological Nitrogen Fixation

This study experimentally reconstructs an ancestral nitrogenase enzyme and shows it strictly requires ATP hydrolysis for N2 reduction, decoupling cofactor selection from environmental availability.

A CRISPR interference system for the nitrogen-fixing bacterium Azotobacter vinelandii

This paper develops a CRISPR interference system in Azotobacter vinelandii to silence nitrogen fixation genes and demonstrates its utility for combinatorial gene expression studies.

A beneficial synonymous substitution in EF-Tu is contingent on genetic background

The paper identifies a beneficial synonymous mutation in EF-Tu that increases mRNA and protein levels but shows fitness benefits dependent on genetic background.

A hybrid nitrogenase with regulatory elasticity in Azotobacter vinelandii

The paper shows that reducing trace metal and electron resources to nitrogenase allows engineered Azotobacter vinelandii to recover wild-type growth with a reduced nitrogenase variant.

The nitrogenase G-subunit is an ancient orphan protein that drove the ecological expansion of nitrogen fixation

The paper investigates the evolutionary origin and ecological impact of the nitrogenase G-subunit, showing its role in enabling nitrogen fixation under changing environmental conditions.

Nitrogenase resurrection and the evolution of a singular enzymatic mechanism

This study resurrects ancient nitrogenase enzymes and shows their in vivo functionality and reversible dinitrogen reduction mechanism, suggesting evolutionary constraints in catalyzing this reaction.

Earliest photic zone niches probed by ancestral microbial rhodopsins

This study reconstructs the paleobiological history of ancestral microbial rhodopsins by combining phylogenetic analysis with environmental modeling to infer their functional roles and spectral tuning in early Earth niches.

Reconstruction of nitrogenase predecessors suggests origin from maturase-like proteins

This study reconstructs the evolutionary origins of nitrogenase enzymes, suggesting they evolved from maturase-like proteins rather than the other way around.

Resurrected Rubisco suggests uniform carbon isotope signatures over geologic time

The paper resurrects an ancient RuBisCO enzyme to test if uniform carbon isotope signatures are consistent across geological time, finding support for uniformitarian assumptions with caveats.

Effects of CO2 and RuBisCO concentration on cyanobacterial growth and carbon isotope fractionation

This study investigates how CO2 and RuBisCO concentration affect cyanobacterial growth and carbon isotope fractionation by engineering a RuBisCO-overexpressing mutant strain.

Evolutionary Stalling and a Limit on the Power of Natural Selection to Improve a Cellular Module

This study shows that natural selection can stall in improving a cellular module, the translation machinery, due to epistasis and depletion of beneficial mutations in E. coli.

Reconstructing the Evolutionary History of Nitrogenases: Evidence for Ancestral Molybdenum-Cofactor Utilization

This study reconstructs the evolutionary history of nitrogenases, finding that ancient nitrogenases likely used molybdenum cofactors, with implications for early biogeochemical cycles.

Resurrecting ancestral genes in bacteria to interpret ancient biosignatures

This paper resurrects ancestral bacterial carbonic anhydrase proteins to link ancient environmental conditions with biosignatures preserved in the geological record.

Functional constraints on replacing an essential gene with its ancient and modern homologs

This study replaces the essential tufA gene in E. coli with extant and ancestral homologs, showing that functional transfer depends on the presence of tufB and evolutionary distance.