The target of rapamycin complex 1 (TORC1) is the central controller of growth in eukaryotic cells. As one of the downstream targets of TORC1, the pro

Second-generation bioethanol from food industry lignocellulosic residues offers a promising route toward low-carbon, circular bioenergy systems. However, the reported environmental impacts differ markedly across studies, challenging efforts to assess the true sustainability of these waste-derived bioethanol routes. This review synthesizes current knowledge on the production of bioethanol from key agro-industrial wastes including oil palm empty fruit bunches, sugarcane bagasse, brewers’ spent grain, spent coffee grounds, tea waste, citrus residues, and potato peel waste. We outline feedstock characteristics, availability, and prevailing management practices, and map the principal biochemical conversion routes to identify process steps that drive environmental performance. A systematic comparison of life cycle assessments reveals substantial methodological heterogeneity across functional units, system boundaries, allocation procedures, and impact assessment methods. Nonetheless, consistent hotspots emerge, particularly associated with pretreatment severity, enzyme production, thermal energy demand, and co-product handling. The review highlights robust cross-study trends, pinpoints methodological gaps, and proposes recommendations for harmonized LCA practice. By integrating technological and methodological perspectives, this work aims to support the development and policy uptake of sustainable, waste-based bioethanol within circular bioeconomies.

ATP synthase uses a rotary mechanism to couple transmembrane proton translocation to ATP synthesis and hydrolysis, which occur at the catalytic sites in the β subunits. In presence of Mg²⁺, the three catalytic sites of ATP synthase have vastly different affinities for nucleotides, and the position of the central γ subunit determines which site has high, medium, or low affinity. Affinity differences and their changes as rotation progresses underpin the ATP synthase catalytic mechanism. Here, we used a series of variants with up to 45- and 60-residue-long truncations of the N- and C-terminal helices of the γ subunit, respectively, to identify the segment(s) responsible for the affinity differences of the catalytic sites. We found that each helix carries an affinity-determining segment of ~ 10 residues. Our findings suggest that the affinity regulation by these segments is transmitted to the catalytic sites by the DELSEED-loop in the C-terminal domain of the β subunits. For the N-terminal truncation variants, presence of the affinity-determining segment and therefore emergence of a high-affinity binding site resulted in wild-type-like catalytic activity. At the C-terminus, additional residues outside of the affinity-determining segment were required for optimal enzymatic activity. Alanine substitutions revealed that the affinity changes of the catalytic sites required no specific interactions between amino acid side chains in the γ and α₃β₃ subunits but were caused by the presence of the helices themselves. Our findings help unravel the molecular basis for the affinity changes of the catalytic sites during ATP synthase rotation.