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Brevibacillus thermoruber strain Nabari cells grow as widely spreading dendritic colonies on reasoner's 2A‐agar (1.5%) plates at around 55°C but as small motile colonies at 37°C. Motile colonies can be divided into colonies that move in straight or curved lines over long distances (wandering colonies), and colonies that rotate at a fixed location (rotating colonies). The addition of surfactant to the agar medium greatly increased the frequency of wandering colonies and facilitated the study of such colonies. The morphology of the wandering colonies varied: circular at the tip and pointed at the back, lemon‐shaped with pointed ends, crescent‐shaped, bullet‐shaped, fish‐like, and so on. A single colony may split into multiple colonies as it moves, or multiple colonies may merge into a single colony. The most surprising aspect of the movement of wandering colonies was that when a moving colony collides with another colony, it sometimes does not make a U‐turn, but instead retreats straight back, as if bouncing back. The migration mechanisms of wandering colonies are discussed based on optical microscopic observations of swimming patterns of single cells in water and scanning electron microscopy of the arrangement of bacterial cells in wandering colonies. [ABSTRACT FROM AUTHOR]

The gene corresponding to the N-terminal glycoside hydrolase family 43 (GH43) module is expressed in Escherichia coli and the gene product is characterized. The results have shown that exo-beta-1,3-galactanases are one of the components of cellulosomes and that the enzymes are widely distributed in nature.

Research has been conducted on the transgenic plant breeding. The possibility of breeding transgenic plants which degrade chloroaromatic compounds in soil and surface water has been investigated and the results of the chlorocatechol-degrading gene expression in these plants are reported.

The cellulosomal alpha-galactosidase Aga27A of Clostridium josui is a catalytic domain of glycoside hydrolases and a dockerin domain involved in the cellulosome assembly.

The cloning and DNA sequencing of the cipA gene encoding the scaffolding protein and the celD gene of Clostridium josui were studied. The molecular architecture of C. josui CipA was similar to those of the scaffolding proteins reported in other types of Clostridium bacteria, but was smaller in size. N-terminal amino acid sequence analysis of the C. josui cellulosomal proteins indicated that both CipA and CelD are major components of the cellulosome.

Researchers cloned and sequenced the arsenic resistance operon (ars) from plasmid pKW301 of Acidiphilium multivorum AIU 301. The amino acid sequences of the ars gene products were homologous to the amino acid sequences of the gene products of Escherichia coli plasmid R773 and IncN plasmid R46. Analysis showed that the ars mRNA started at a position 19 nucleotides upstream from the arsR ATG in E. coli. Inactivation of the ars gene resulted in constitutive expression of the ars genes, suggesting that arsR of pKW301 controls the expression of this operon.

Research was conducted to characterize the chitinase gene with its translated product from an anaerobic chitinolytic bacterium called Clostridium paraputrificum. A DNA sequencer was utilized to perform nucleotide sequencing while chromosomal DNA was isolated and separated on an agarose gel. Results indicated that the deletion of the chitin-binding domain from chitinase B did not influence enzyme activities geared toward colloidal chitin.

A study was done to determine the nucleotide sequence and structural properties of xynC. Two major isolates were found to be homologous to the thermostabilizing domain. The C-terminus separated from the catalytic domain by a short linker sequence included a dockerin domain responsible for cellulosome assembly. The deduced Nterminal sequence contains a sequence similar to the signal found in the C-terminal region.

Four genes involved in porphyrin synthesis in the anaerobic bacterium Clostridium josui have been identified. The hemA, hemB, hemC and hemD genes are homologous to similar genes in E. coli and Bacillus subtilis. They appear to be controlled by one operon. Portions of the C-terminus of the hemA protein and the N- terminus of the hemD protein are similar to the E. coli CysG protein. HemA and hemD may be bifunctional enzymes.

A newly identified carbohydrate-binding module for the function of CelB (BH0603) from the Alkalphilic bacterium Bacillus halodurans was studied. It was found that the recombinant PfamB module bound to Avicel was essential for CelB hydrolytic function.