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The identification, isolation and characterization of the nitroreductase genes, nprA and nprB, involved in 2,4-dinitrophenol reduction in the phototrophic bacterium Rhodobacter capsulatus B10 are described. The induction of the nprA gene by paraquat and by an oxidized redox status in the cell indicates that the SoxRS system can also be implicated in controlling nprA gene expression.

Deletion of the ace1 gene, encoding the cellulase regulator ACEI, increases the expression of cellulase and xylanase genes in Trichoderma reesei, suggesting that ACEI functions as a repressor of cellulase and xylanase syntheses. Furthermore, results point to yet another activator, ACEII, similar to ACEI in action, existing in T. reesei.

Results demonstrate that expression of a cluster of three genes in Bifidobacterium lactis are governed by transcriptional regulation and are induced by sucrose and raffinose and repressed by glucose. Data indicate that ScrR gene is a positive regulator.

Results indicate that in Bradyrhizobium japonicum nitrogen-fixing symbiosis in soy bean plant is regulated via nod gene expression and multiple mechanisms. Data show that three global regulatory families comprising of MeR, two-component, and LysR together with signals derived from the symbionts themselves mediate the nodulation process.

Research has been conducted on iron homeostasis of filamentous fungus Aspergillus nidulans which is regulated by the negative-acting GATA factor SREA. Results demonstrate that the expression of heme-containing metalloreductase-encoding gene is upregulated by the independent of SREA iron limitation which indicates that the iron-regulatory mechanism does not involve SREA.

Research describes the usage of gene replacement technology to improve the production of lactic acid by Lactobacillus helveticus CNRZ32. Results show that in the genetically engineered strains lactic acid production was higher by 53 to 93% as compared to the wild-type strain.

The kinetics of expression and repression of the Aspergillus awamori 1,4-beta-endoxylanase A (exlA) gene was investigated at the mRNA and protein levels. Northern blot analysis of pulsed samples revealed that kinetics of mRNA synthesis of exlA is similar to those of the Thermomyces lanuginosa lipase and Escherichia coli beta-glucorinidase genes. Analysis of the pulsed samples under continuous culture conditions revealed that repression of the exlA gene occurs approximately one hour after mRNA expression.

The kinetics of induction of the nisin A (nisA) gene in Lactococcus lactis was investigated by comparison with the expression of the gusA gene in L. lactis NZ9800, which contains a deletion in the nisA gene. Transcriptional and translational fusion with a nisA promoter revealed a significant relationship between the amount of nisin in the medium and beta-glucoronidase activity, indicating that enzyme production is linearly dependent on nisA expression.

Heterologous hybridization facilitates the cloning of the Aspergillus terreus gla1 gene, which encodes a glucoamylase. Transcriptional analysis of the gene reveals the presence of a protein having a C-terminus starch-binding domain and N-terminal catalytic domain. Examination of the influence of carbon sources on gla1 regulation reveals that starch and maltose stimulate the expression of the gene, while glucose represses the expression.

Experimental studies reveal that H2O2 and various chemicals regulate the expression of manganese peroxidase (MnP) in nitrogen-limited cultures of Phanerochaete chrysosporium at the level of gene transcription. Northern blot analysis reveals that simultaneous induction by H2O2 and Mn leads to higher production of mnp mRNA compared to that due to induction by H2O2 alone. Heat shock increases the accumulation of mnp mRNA, and accumulation of mnp mRNA due to molecular oxygen is significantly smaller compared to that with H2O2 and heat shock. Simultaneous induction with Mn and H2O2 increases the MnP activity.

Results show that sulfate is the source of sulfur for the biosynthesis of penicillin in the bacterium. There is a direct relationship between levels of mRNA of the sulfate transporter genes and the sulfate concentration. However, strains exhibiting high-penicillin yield transcribe sutB efficiently in the presence of high sulfate.

The cloning and sequencing of cDNA encoding AoVps10 from the filamentous fungus Aspergillus oryzae is described. The results have shown that AoVps10 has played a role in the regulation of heterologous protein secretion in Aspergillus oryzae and is involved in the vacuolar protein degradation through the Golgi apparatus.

The first high-resolution metabolomics time series analysis of various strains of Streptomyces coelicolor exposed to salt stress is presented. The results indicated that a large fraction of amino acids is upregulated in response to the salt stress similar to proline/glycine-containing di- and tripeptides.

A recombinase-based in vivo expression technology (IVET) was adapted to study the genes activated in Bacillus cereus ATCC 14579 during growth at low temperatures. The study demonstrated the feasibility of a promoter trap strategy for identifying cold-induced genes and also outlined the different processes involved in B. cereus cold acclimation.

The ferric uptake regulator (Fur)- and iron-regulated genes are identified in Listeria monocytogenes by DNA microanalysis using a fur mutant and its isogenic parent. The results have shown that Fur and PerR proteins have negatively regulated fur and that under iron-limited conditions, PeR is needed for the negative regulation of genes controlled by Fur.

Several genome sequence analyses are conducted to explain the various mechanisms and features exhibited by Flavobacterium johnsoniae, a polysaccharide-digesting gliding bacterium. The numerous genes that are required for the formation of the outer membrane pigments in the bacterium are also identified.

The first study evidence for the differential production of the two phenazines in the strains M18 and PAO1 which is related to the temperature-dependent and strain-specific expression patterns of phzM, a gene involved in the conversion of phenazine-1-carboxylic acid (PCA) to pyocyanin (PYO) is presented. The differential production of the phenazines PCA and PYO by strains M18 and PAO1 might be attributed to consequence of selective pressure imposed on P. aeruginosa PAO1 and its relative M18 in the two different niches over a long evolutionary process.

The diversity in regulatory phenotypes among Lactococcus lactis strains isolated from dairy and nondairy origin is examined. The results have represented the most extensive diversity analysis of regulatory phenotypes within a single bacterial species and they have highlighted the importance of the availability of the screening procedures for industrially relevant enzyme activities in models mimicking application conditions.

A gene cluster is identified that has encoded the enzymes and regulatory and transporter proteins for the different steps in the biosynthesis of extracellular polysaccharides (EPS) of the probiotic strain Lactobacillus rhamnosus GG. The characterization of the welE mutant has shown that deprivation of the long, galactose-rich EPS molecules has resulted in an increased adherence and biofilm formation capacity of Lactobacillus rhamnosus GG, because of less shielding of adhesins such as fimbria-like structures.

An in vivo transposition system was used to identify novel regulators that influenced undecylprodigiosin (Red) production in Streptomyces coelicolor M145. The results from reverse transcription-PCR analysis revealed that RrdA negatively regulated Red production by controlling redD mRNA abundance, while no change was observed at the transcript level of the actinorhodin (Act)-specific activator gene, actII-orf4.

The identification and functional analysis of PA1727, a bis-(3'-5')-cyclic-dimeric-GMP (c-di-GMP)-synthesizing enzyme isolated from Pseudomonas aeruginosa which is involved in regulation of alginate production is described. The results indicated that MucR specifically regulates alginate biosynthesis by activation of alginate production through generation of a localized c-di-GMP pool in the vicinity of Alg44.

A global expression analysis and phenotypic studies were performed to understand the regulatory role of SMc04032, one of the orphan LuxR homologs of Sinorhizobium meliloti. The analysis identified LuxR-type protein NesR as a regulator of the active methyl cycle of S. meliloti and hence influenced nutritional and stress response activities in Sinorhizobium meliloti.

The strains [P.sub.phoB]::[P.sub.tac] and [P.sub.pstS]::[P.sub.tac] from Pho regulon in Escherichia coli are used to characterize phenotypes resulting from various [DELTA]phoU mutations in plasmids. The experimental results suggested that PhoU plays a significant role in controlling the abundance of the Pst[SCAB.sub.2] transporter through the PhoBR two-component signaling pathway and its activity.

Four desiccation-sensitive mutants of Sinorhizobium meliloti Rm1021 are identified, where three regulatory genes and one DNA repair gene have contributed to normal Sinorhizobium meliloti desiccation resistance. The studies have shown that uvr gene-mediated DNA repair and the regulation of stress-induced pathways are very vital for desiccation resistance.

A time series of whole-genome transcription profiling of Escherichia coli K-12 W3110 is performed during a carbon-limited fed-batch process to identify dynamic sequence of diverse carbon limitation responses and provide global view of utilization of cellular and extracellular resources. The findings from the detailed study of the genetic regulation of bacterial metabolism could provide useful insight into manipulation of the carbon flux in technical production processes.

The involvement of nodulation gene regulation and quorum sensing in the restriction of nodulation by Bradyrhizobium japonicum is discussed. Results suggest the usefulness of nodD2 mutant of B. japonicum for enhancing soybean nodulation at high inoculum densities.

Research has been conducted on EIIAB (super)Man protein of Streptococcus mutans UA159. The role of this protein in carbohydrate transport, in gene expression control and in virulence determinant regulation has been investigated, and the results are reported.

Research has been conducted on recombinant Escherichia coli which produces human insulin-like growth factor I fusion protein. The transcriptosome profiles of E. coli have been investigated via the use of DNA microarrays, and the results demonstrate that transcriptosome profiling provides information for designing engineered strains with enhanced performance.

Research has been conducted on secreted protein glycosylation. The study of the regulation and limiting factors in proteins' glycosylation has been carried out via overexpression of mgp1 and dpm1 genes from Trichoderma reesi, which encode GTP:mannose-1-phosphate guanyltrasferase and dolichyl phosphate mannose synthase, in T. reesi, and the data demonstrate the regulatory role of cellular GDP-mannose in protein glycosylation.

The authors discus the study on stationary-phase-inducible sigma factor RpoS which regulates stress respones in Salmonella. They have examined the rpoS mutants' status in human clincal isolates, and have suggest that Salmonella serotype Typhimurium rpoS mutants are counterselective.

Research has been conducted on gene expression regulation. The authors demonstrate that P1 temperature-sensitive C1 repressor can control gene expression via the use of promoters in pathogenic gram-positive species.

Research has been conducted on pectate lyase. The role of nitrogen source and external pH in secretion of virulence factor pectate lyase has been examined, and the hypothesis that nitrogen source availability and ambient pH are independent signals for genes' transcriptional regulation has been tested.

Research has been conducted on Lactococcus lactis growth in milk. The authors have demonstrated that double inactivation of aminotransferases AraT and BcaT, isolated from L. lactis, reduce L. lactis growth in milk.

Research has been conducted on regulatory genes from trichothecene mycotoxin-producing Fusarium species which is required for trichothecene biosynthesis. Results demonstrate that these genes regulate overlapping set of genes which include multiple genes for primary and secondary metabolism.

Results reveal that TsaR, the LysR-type regulator of the tsa operon, interacts at a region of the operon that blocks tsaR transcription in the absence of p-toluenesulfonate, but in its presence, TsaR shifts to different region relieving tsaR transcription blockade and transcription of the tsa operon.