Bacterium electrode

Biological principles are also used in enzyme electrodes, where the sensor (usually an ion-selective electrode) is covered by a polymeric carrier containing an enzyme [32]. The determinand reacts in the enzyme layer yielding a product that causes a signal in the sensor. The bacterium electrode is based on a similar principle [84], as are electrodes using tissue in place of the enzyme layer [2]. 

A representative example of a biocatalytic membrane electrode is an electrode for L-arginine The bacterium streptococcus faecium is immobilized on the gas permeable membrane of an ammonia electrode. Arginine deiminase in the bacterium catalyzes the following reaction... 

The electrodes were powered by an audio amplifier whose input frequency was set by an audio oscillator. The impedance of the chamber, 6 Q, was perfectly matched to the output impedance of the amplifier. To test the proper functioning of the apparatus before putting in mammalian cells, we used the common bacterium Escherichia coli. These, and prokaryotic cells generally, do not show mitotic figures in division. After the bacterial population reached a steady state, the electric field was turned on. The density... 

Entrapment of Bacterium cadaveris on an ammonia electrode using dialysis membranes L-aspartate [63]... 

In experiments initially designed to study the effects of electric fields upon the growth of the bacterium Escherichia coli E. coli), Rosenberg et al. (109) observed the unusual phenomenon of filamentous growth. The bacterial cells, which normally divide rapidly, grew to 300 times their usual size and did not divide. This observation was eventually found to derive from the presence of Pt(II) and Pt(IV) ammine chloride complexes formed in situ by electrolysis at the platinum electrodes. Further studies showed one cause of the filamentation to be cis-diamminedichloroplatinum(II) cis-... 

In a recent papet the chronoamperometry has been used to smdy the competitive occurrence of an electrochemical reaction of the mediators at the electrode and their chemical reaction with the cofectors of the Reaction Center of the photosyntheric bacterium Rhodobacter Sphaeroides. The overall process is modeled by a set of differential equations that allow the calculation of the kinetic constants of the chemical and elearochemical reactions respeaively. 

Another example deals with amino acid analysis using immobilized specific microorganisms in combination with selective electrodes (35). Thus, glutamine could be analyzed by an electrode consisting of a potentiometric ammonia gas sensor and a layer of the bacterium Sarcina flava (American type culture collection 147) trapped in the volume between a NHo-permeable membrane on the surface of the electrode and a dialysis membrane in contact with the surrounding solution (Fig. 10). Using this electrode, steady state potentials were reached within 5 minutes. 

Kalimuthu et al. reported the catalytic voltammetry of SDH from the soil bacterium Sinorhizobium meliloti (SorT) at a glassy carbon electrode using the artificial electron acceptor ferrocenium methanol (FM). As mentioned... 

Fe-4S], [Zn3Fe-4S], and [Cd3Fe-4S] clusters respectively [35, 36]. This parhcular example, ferredoxin III isolated from a sulfate reducing bacterium Desulfovibrio ajricanus, contains two Fe-S clusters, a [4Fe-4S] cluster that is inert and a [3Fe-4S] cluster that is reactive and has a high affinity for various metal ions. The protein is adsorbed on a PGE electrode in the presence of polymyxin, and on addition of metal ions the reaction is observed... 

Summers ZM, Gralnick JA, Bond DR. Cultivation of an obligate Fe(It)-oxidizing bthoautotrophic bacterium using electrodes. MBio 2013 4(l) e00420-12. 

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