Nostosin G and Spiroidesin B from the Cyanobacterium sp. NIES-1697.

Chemical investigation of the cyanobacterium sp. NIES-1697 afforded nostosin G (), a linear tripeptide, spiroidesin B (), and two known compounds, anabaenopeptins I () and J (). Planar structures and absolute configurations for and were determined by 2D NMR, HRMS, Marfey's methodology, chiral-phase HPLC, and enzymatic degradation.

Wewakazole B, a Cytotoxic Cyanobactin from the Cyanobacterium Moorea producens Collected in the Red Sea.

A mass spectrometry (MS)-guided isolation has led to the purification of a new cyanobactin, wewakazole B (1), along with the known compound curacin D from a Red Sea Moorea producens. The planar structure of 1 was elucidated using a combination of NMR and MS techniques. After ozonolysis and acid hydrolysis, the absolute configurations of the amino acid components of 1 were determined by chiral-phase LC-MS and HPLC analyses.

An N-terminal region of a Myb-like protein is involved in its intracellular localization and activation of a gibberellin-inducible proteinase gene in germinated rice seeds.

The expression of the gene for a proteinase (Rep1) is upregulated by gibberellins. The CAACTC regulatory element (CARE) of the Rep1 promoter is involved in the gibberellin response. We isolated a cDNA for a CARE-binding protein containing a Myb domain in its carboxyl-terminal region and designated the gene Carboxyl-terminal Myb1 (CTMyb1).

cDNA cloning and characterization of vanadium-dependent bromoperoxidases from the red alga Laurencia nipponica.

The marine red alga genus Laurencia is one of the richest producers of unique brominated compounds in the marine environment. The cDNAs for two Laurencia nipponica vanadium-dependent bromoperoxidases (LnVBPO1 and LnVBPO2) were cloned and expressed in Escherichia coli. Enzyme assays of recombinant LnVBPO1 and LnVBPO2 using monochlorodimedone revealed that they were thermolabile but their Km values for Br(-) were significantly lower than other red algal VBPOs.

Efficacy of forming biofilms by naphthalene degrading Pseudomonas stutzeri T102 toward bioremediation technology and its molecular mechanisms.

In natural environments, bacteria often exist in close association with surfaces and interfaces. There they form "biofilms", multicellular aggregates held together by an extracellular matrix. The biofilms confer on the constituent cells high resistance to environmental stresses and diverse microenvironments that help generate cellular heterogeneity.

A truncated form of SpoT, including the ACT domain, inhibits the production of cyclic lipopeptide arthrofactin, and is associated with moderate elevation of guanosine 3',5'-bispyrophosphate level in Pseudomonas sp. MIS38.

Arthrofactin is a biosurfactant produced by Pseudomonas sp. MIS38. We have reported that transposon insertion into spoT (spoT::Tn5) causes moderate accumulation of guanosine 3',5'-bispyrophosphate (ppGpp) and abrogates arthrofactin production.

Diversity of nonribosomal peptide synthetases involved in the biosynthesis of lipopeptide biosurfactants.

Lipopeptide biosurfactants (LPBSs) consist of a hydrophobic fatty acid portion linked to a hydrophilic peptide chain in the molecule. With their complex and diverse structures, LPBSs exhibit various biological activities including surface activity as well as anti-cellular and anti-enzymatic activities. LPBSs are also involved in multi-cellular behaviors such as swarming motility and biofilm formation.

Sustainable biodegradation of phenol by Acinetobacter calcoaceticus P23 isolated from the rhizosphere of duckweed Lemna aoukikusa.

Phenol-degrading bacteria were isolated from the rhizosphere of duckweed (Lemna aoukikusa) using an enrichment culture method. One of the isolates, P23, exhibited an excellent ability to degrade phenol and attach to a solid surface under laboratory conditions. Phylogenetic analysis revealed that P23 belongs to the genera Acinetobacter and has the highest similarity to Acinetobacter calcoaceticus.

Identification and characterization of the genes responsible for the production of the cyclic lipopeptide arthrofactin by Pseudomonas sp. MIS38.

Pseudomonas sp. MIS38 produces an effective biosurfactant named arthrofactin, which is a cyclic lipopeptide synthesized by a mega complex composed of three nonribosomal peptide synthetases. In order to gain insight into the control mechanism of arthrofactin production, a Tn5 mutant library was constructed and screened for arthrofactin-deficient mutants.

The role of urease activity on biofilm formation by Staphylococcus sp. T-02 isolated from the toilet bowl.

Urolith, which consists of dirty yellow-colored attachments on the toilet bowl, is associated with a variety of odorous chemicals, including ammonia, and causes disadvantages in daily life. Although largely it is derived from microorganisms, little is known about the microbial processes underlying the formation of urolith. In order to gain insight into the types and the activities of microorganisms present in urolith, culturable bacteria were isolated, identified, and physiologically characterized.

Biofilm formation and proteolytic activities of Pseudoalteromonas bacteria that were isolated from fish farm sediments.

In order to save natural resources and supply good fishes, it is important to improve fish-farming techniques. The survival rate of fish fry appears to become higher when powders of foraminifer limestone are submerged at the bottom of fish-farming fields, where bacterial biofilms often grow. The observations suggest that forming biofilms can benefit to keep health status of breeding fishes.

Identification of alkane hydroxylase genes in Rhodococcus sp. strain TMP2 that degrades a branched alkane.

Rhodococcus sp. TMP2 is an alkane-degrading strain that can grow with a branched alkane as a sole carbon source. TMP2 degrades considerable amounts of pristane at 20 degrees C but not at 30 degrees C.

Functional analysis of a pyoverdine synthetase from Pseudomonas sp. MIS38.

Fluorescent Pseudomonas sp. MIS38 produces a cyclic lipopeptide, arthrofactin. Arthrofactin is synthesized by a unique nonribosomal peptide synthetase (NRPS) with dual C/E-domains.

In vivo characterization of tandem C-terminal thioesterase domains in arthrofactin synthetase.

Macrocyclization of a peptide or a lipopeptide occurs at the last step of synthesis and is usually catalyzed by a single C-terminal thioesterase (Te) domain. Arthrofactin synthetase (Arf) from Pseudomonas sp. MIS38 represents a novel type of nonribosomal peptide synthetase that contains unique tandem C-terminal Te domains, ArfC_Te1 and ArfC_Te2.

Common mechanisms regulating expression of rice aleurone genes that contribute to the primary response for gibberellin.

During germination of cereal seeds, aleurone cells respond to gibberellins (GA) by synthesizing and secreting hydrolytic enzymes that mobilize the reserved nutrients. It has been shown that products of early GA response genes, like a transcription factor GAMyb, act as key molecules leading to this regulation. Pivotal roles of GAMyb on expression of hydrolase genes have been well documented, whereas regulation of GAMyb expression itself remains obscure.

Phylogenetic analysis of condensation domains in the nonribosomal peptide synthetases.

Condensation (C) domains in the nonribosomal peptide synthetases are capable of catalyzing peptide bond formation between two consecutively bound various amino acids. C-domains coincide in frequency with the number of peptide bonds in the product peptide. In this study, a phylogenetic approach was used to investigate structural diversity of bacterial C-domains.

Functional dissections between GAMYB and Dof transcription factors suggest a role for protein-protein associations in the gibberellin-mediated expression of the RAmy1A gene in the rice aleurone.

In the germinated cereal aleurone layer, gibberellic acids (GA) induce expression of a number of genes encoding hydrolytic enzymes that participate in the mobilization of stored molecules. Previous analyses suggest that the key events controlling the GA-regulated gene expression in the aleurone are formation of active transcription machinery referred to as the GA responsive complex, followed by recruiting GAMYB. In general, bipartite promoter contexts composed of the GA-responsive element and the pyrimidine box are observed within the regulatory regions of cereal GA-responsive genes.

Cloning and characterization of cDNA of the GPI-anchored purple acid phosphatase and its root tissue distribution in Spirodela oligorrhiza.

A cDNA clone of the glycosylphosphatidylinositol (GPI)-anchored purple acid phosphatase (PAP) has been obtained by a combination of cDNA library screening and 5' rapid amplification of cDNA ends from Spirodela oligorrhiza plants grown under phosphate-deficient (-P) conditions. The open reading frame of the S. oligorrhiza PAP cDNA consists of 1 365 bp encoding a 455 amino acid protein.