The plasmodium of Physarum polycephalum is a large single cell visible with the naked eye. When inoculated on a substrate with attractants and repellents the plasmodium develops optimal networks of protoplasmic tubes which span sites of attractants (i.e. nutrients) yet avoid domains with a high nutrient concentration. It should therefore be possible to program the plasmodium towards determinist...

The activity of transcription factors modulates several neural pathways that mediate complex behaviors. We describe here the role of the POU transcription factor UNC-86 in the olfactory behavior of Caenorhabditis elegans. unc-86-null mutants are defective in response to odor attractants but avoid odor repellents normally. Continuous UNC-86 activity is necessary for maintenance of odortaxis beha...

Betaine, L-alanine, L-glutamic acid, L-arginine, glycine and inosine are known as dietary feeding attractants for many fish species. However, these additives also have very important physiological functions within the animal body. For example, betaine given singly or mixed with other attractants has been found to have a positive effect on fish growth and survival rate. Betaine is also a very im...

UNLABELLED The malaria parasite Plasmodium falciparum contains a nonphotosynthetic plastid organelle that possesses plant-like metabolic pathways. Plants use the plastidial isoprenoid biosynthesis pathway to produce volatile odorants, known as terpenes. In this work, we describe the volatile chemical profile of cultured malaria parasites. Among the identified compounds are several plant-like te...

Plasmodium of slime mould Physarum polycephalum is a large single celled organism visible unaided by the eye. This slime mould is capable of optimising the shape of its protoplasmic networks in spatial configurations of attractants and repellents. Such adaptive behaviour can be interpreted as computation. When exposed to attractants and repellents, Physarum changes patterns of its electrical ac...

The intracellular signal that produces changes in swimming behavior when bacteria encounter attractants or repellents has not previously been identified. We suggest, based on the following lines of evidence, that cyclic GMP (cGMP) is involved in this signaling process in chemotaxis by Escherichia coli. (i) The addition of attractants to bacteria causes a transient increase in the intracellular ...

Paramecium tetraurelia is attracted and repelled by a variety of chemical stimuli. The attractants probably signify the presence of nutrients. For attractants, there are at least three signal transduction pathways that all lead to a hyperpolarization of the cell that results in relatively fast and smooth swimming. The three pathways differ in stimuli, receptor mechanisms and second messengers. ...

The interaction of isovaleraldehyde, an attractant, with zoospores of the fungus Phytophthora palmivora was investigated by using binding techniques. The amount of isovaleraldehyde bound diminished with time, an effect that may be related to sensory adaptation. In addition to non-specific binding, specific and saturable isovaleraldehyde binding was demonstrated. Cooperativity occurred at interm...

A plasmodium of acellular slime mould Physarum polycephalum is a large single cell with many nuclei. Presented to a configuration of attracting and repelling stimuli a plasmodium optimizes its growth pattern and spans the attractants, while avoiding repellents, with efficient network of protoplasmic tubes. Such behaviour is interpreted as computation and the plasmodium as an amorphous growing b...