membranlos

Membranlos is a term used in some languages to describe something that lacks a surrounding membrane. In biology, membranlos refers to structures or systems that operate without a lipid bilayer, in contrast to membrane-bound organelles such as mitochondria or the endoplasmic reticulum. The term is not a formal scientific category, but it is used to discuss common characteristics of membrane-free organization in cells and in synthetic models.

Membraneless organelles: Within cells, several compartments do not enclose themselves in a membrane. These membraneless organelles form through concentration-dependent interactions, often described as liquid-liquid phase separation, among proteins and nucleic acids. Examples include the nucleolus, stress granules, and P-bodies. These condensates can assemble and dissolve in response to cellular conditions and carry out specialized functions without a surrounding lipid envelope.

Origin of life and synthetic biology: In origin-of-life studies and in synthetic systems, membraneless compartments are explored as models of early cell-like organization. Coacervates and other phase-separated bodies can concentrate reactants and catalyze chemistry without lipid membranes.

Applications and challenges: In materials science and biotechnology, membraneless approaches can enable rapid exchange with the environment and simpler manufacturing, but may face issues of stability, selectivity, and control over composition.

See also: Membrane-bound organelle; Membrane-less organelle; Phase separation; Protocell; Lipid bilayer.