The effect of chemotactic substances, secreted by Escherichia coli, on the cellular slime molds was studied by deposition of bacteria near myxamoebae populations. Droplets of a bacterial suspension and a myxamoebae suspension were placed separately, at predetermined distances from each other, on a hydrophobic agar surface of low rigidity. Myxamoebae remained confined inside the droplets, except...

Most naturally occurring olfactory signals do not consist of monomolecular odorants but, rather, are mixtures whose composition and concentration ratios vary. While there is ample evidence for the relevance of complex odor blends in ecological interactions and for interactions of chemicals in both peripheral and central neuronal processing, a fine-scale analysis of rules governing the innate be...

The archaebacterium Methanococcus voltae, was shown to be chemotactic. Acetate, isoleucine, and leucine were identified as attractants; whereas histidine was not an attractant. A motile, generally nonchemotactic mutant was isolated.

BACKGROUND British mosquito population distribution, abundance, species composition and potential for mosquito disease transmission are intimately linked to the physical environment. The presence of ponds and water storage can significantly increase the density of particular mosquito species in the garden. Culex pipiens is the mosquito most commonly found in UK gardens and a potential vector of...

Shortly after Kangas et al. (1) reported that a-terpineol was the major component of a primary host attractant for Blastophagus piniperda L., Silverstein, Rodin, and Wood (2) revealed the identity of three other terpene alcohols that play a role in the orientation of bark beetles. However, Silverstein et al. concluded, from laboratory bioassay, that a mixture of the three terpene alcohols they ...

Protection of Norway spruce stands using anti-attractants was tested during an outbreak bark beetles (Ips typographus) in their spring flight. The aims this study were as follows: (1) to test the proposed experimental design for tree protection; (2) evaluate height-specific alternatives dispenser installation on trees; and (3) efficiency protection measures under beetle infestation drought stre...

It has previously been reported that the alpha-proteobacterium Azospirillum brasilense undergoes methylation-independent chemotaxis; however, a recent study revealed cheB and cheR genes in this organism. We have constructed cheB, cheR, and cheBR mutants of A. brasilense and determined that the CheB and CheR proteins under study significantly influence chemotaxis and aerotaxis but are not essent...