Sugar chemotaxis

High afihnity receptor protein located in the so-called periplasmic space between the inner membrane and the cell wall participates in active transport of nutrients or their analogues. Certain types of sugar chemotaxis are also initiated in the periplasmic space, especially galactose chemotaxis. Table 1 summarizes various types of transport and other functions of the bacterial cell in terms of bioenergetics (see also references). 

Ermilova EV, Zalutskaya ZM, Gromov BV (1993) Chemotaxis towards sugars in Chlamydomonas reinhardtii. Curr Microbiol 27 47-50... 

Yu, C., Bassler, B. L., and Roseman, S., Chemotaxis of the marine bacterium Vibrio fumissii to sugars. A potential mechanism for initiating the chitin catabolic cascade,./. Biol. Chem., 268, 9405, 1993. 

A rather widespread family of proteins, found in the periplasmic space of gramnegative bacteria, complexes certain small molecules and allows them to be transported through the cell wall or activate chemotaxis. Each of these functions involves a consecutive interaction with specific membrane proteins. The molecules transported are amino acids, sulfate, mono- and oligosaccchrides. In this way ABP complexes L-arabinose (K 0.98 x 10 M), and MBP (maltodextrin-binding protein) complexes maltose (ATj 35 x 10 M) and maltodextrins. It is in this series that are found the strongest possible bonds between sugars and proteins. The dissociation rate ( i 1.5 s ) is indicative of the upper limit of the ionic transport rate. Hydrogen bonds... 

The capillary assay was first described by Pfeffer in the 1880s and standardized and popularized by Adler in the 1970s (20). Some of the most fundamental discoveries about chemotaxis, like the discovery of specific cell-surface chemoreceptors (2) and the identification of attractant amino acids, sugars, and other compounds (21, 22), were made using this assay. 

Adler, J., Hazelbauer, G.L. and Dahl, M.M. (1973). Chemotaxis towards sugars in Escherichia coli.J. Bacteriol. 115, 824-847. 

Adler, J. and Epstein, W. (1974). Phosphotransferase-system enzymes as chemore-ceptors for certain sugars in Escherichia coli chemotaxis. Proc. Natl. Acad. Sd. U.S.A. 71, 2895-2899. 

Jeziore-Sassoon, Y., Hamblin, P.A., Bootle-Wilbraham, C.A., Poole, P.S. and Armitage, J.P. (1998). Metabolism is required for chemotaxis to sugars in Rhodobacter sphaeroides. Microbiology 144, 229-239. 

Loake, G.J., Ashby, A.M. and Shaw, G.H. (1988). Attracdon of Agrobacterium tumefaciens C58G towards sugars involves a highly sensitive chemotaxis system. J. Gen. Microbiol. 134,1427-1432. 

Thoelke, M.S., Casper, J.M. and Ordal, G.W. (1990). Methyl transferin chemotaxis toward sugars by Bacillus subtilis.J. Bacterial. 172, 1148-1150. 

There is no evidence that any of the described methylation transducers are involved in chemotaxis responses to sugars transported by the phosphotransferase (PEP) system (Figure 4.1). The existence of further methylated transducers to account for these sugars has been postulated. Alternatively the phosphorylation that accompanies the uptake of the sugar may act as the transducer. 

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