Prokaryotic life has dominated most of the evolutionary history of our planet, evolving to
occupy virtually all available environmental niches. Extremophiles, especially those thriving …

The origin of life entails a continuum from simple prebiotic chemistry to cells with genes and
molecular machines. Using life as a guide to this continuum, we consider how selection …

A reverse pH gradient is a hallmark of cancer metabolism, manifested by extracellular
acidosis and intracellular alkalization. While consequences of extracellular acidosis are …

Recent physiological and ecological studies have challenged the long-held belief that
microbial metabolism of molecular hydrogen (H2) is a niche process. To gain a broader …

H2 metabolism is proposed to be the most ancient and diverse mechanism of energy-
conservation. The metalloenzymes mediating this metabolism, hydrogenases, are encoded …

Teleost fish possess an adaptive immune system associated with each of their mucosal
body surfaces. Evidence obtained from mucosal vaccination and mucosal infection studies …

Over the last 70 years, prebiotic chemists have been very successful in synthesizing the
molecules of life, from amino acids to nucleotides. Yet there is strikingly little resemblance …

The development of novel, sustainable, and robust food production technologies represents
one of the major pillars to address the most significant challenges humanity is going to face …

Energy conversion of sunlight by photosynthetic organisms has changed Earth and life on it.
Photosynthesis arose early in Earth's history, and the earliest forms of photosynthetic life …

The fixation of inorganic carbon into organic material (autotrophy) is a prerequisite for life
and sets the starting point of biological evolution. In the extant biosphere the reductive …