Algae-bacteria interactions: Evolution, ecology and emerging applications.

http://academic.oup.com/milmed/article-pdf/146/1/60/24125826/milmed-146-1-60.pdf

Biochemical Tests for Identification of Medical Bacteria

The authors set themselves the tasks of showing how evolutionary information is written into gene sequences and describing the methods by which such information can be recovered. In this quite excellent book they succeed, providing a wealth of examples and setting many of them in a historical perspective.

/pdf/molecular-evolution-a-phylogenetic-approach-2swt1benmt.pdf

Molecular Evolution — A Phylogenetic Approach.

Denitrification and aerobic respiration, hybrid electron transport chains and co-evolution

Understanding aerobic denitrification has become an important focus of environmental microbiology. Aerobic denitrification can be performed by various genera of microorganisms and describes the use of nitrate (NO
 3
 -
 ) as oxidizing agents under an aerobic atmosphere. Isolation of aerobic denitrifiers, enzymes involved in aerobic denitrifiers, phylogenetic distribution of aerobic denitrifiers, factors affecting the performance of aerobic denitrifiers, attempts of applications and possible future trends are depicted. The periplasmic nitrate reductase is vital for aerobic denitrifiers and NapA gene may be the proof of aerobic denitrification. Phylogenetic analysis revealed that aerobic denitrifiers mainly belong to α-, β- and γ-Proteobacteria. Aerobic denitrifiers tend to work efficiently at 25 ~ 37°C and pH 7 ~ 8, when dissolved oxygen concentration is 3 ~ 5 mg/L and C/N load ratio is 5 ~ 10. In addition, recent progresses and applications on aerobic denitrifiers are described, including single aerobic reactors, sequencing batch reactor and biofilm reactors. The review attempts to shed light on the fundamental understanding in aerobic denitrification.

Aerobic denitrification: A review of important advances of the last 30 years

Aerobic Denitrification of Pseudomonas putida AD-21 at Different C/N Ratios

The aim of this study was to isolate and identify algicidal bacteria against the dinoflagellate Cochlodinium polykrikoides, and to determine the algicidal activity and algicidal range. During the declining period of C. polykrikoides blooms, seven algicidal bacteria were isolated. The algicidal bacteria against C. polykrikoides were enumerated using the most probable number (MPN) method. The number of algicidal bacteria was high (3.7 × 103 mL−1). Algicidal bacteria were identified on the basis of biochemical and chemotaxonomic characteristics, and analysis of 16S rDNA sequences. Seven algicidal bacteria isolated in this study belonged to the genera Bacillus, Dietzia, Janibacter, and Micrococcus. The most algicidal bacterium, designated Micrococcus luteus SY-13, is assumed to produce secondary metabolites. When 5% culture filtrate of this strain was applied to C. polykrikoides cultures, over 90% of C. polykrikoides cells were destroyed within 6 h. M. luteus SY-13 showed significant algicidal activities against C. polykrikoides and a wide algicidal range against various harmful algal bloom (HAB) species. Taken together, our results suggest that M. luteus SY-13 could be a candidate for controlling HABs.

Isolation, identification, and algicidal activity of marine bacteria against Cochlodinium polykrikoides

Metastasis is the main cause of cancer mortality. In this study, we investigated the effects of surfactin, a cyclic lipopeptide produced by Bacillus subtilis, on cancer metastasis in vitro and the underlying molecular mechanisms involved. Surfactin inhibited the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced invasion, migration and colony formation of human breast carcinoma cells. Western blot analysis, gelatin zymography and reverse transcription-PCR analysis revealed that matrix metalloproteinase-9 (MMP-9) expression and activation was significantly suppressed by surfactin in a dose-dependent manner. Surfactin attenuated TPA-induced nuclear translocation and activation of nuclear factor-κB (NF-κB) and activator protein-1 (AP-1). Furthermore, surfactin strongly repressed the TPA-induced phosphorylation of Akt and extracellular signal-regulated kinase (ERK). Treatment with specific inhibitors of Akt and ERK suppressed MMP-9 expression and activation. These results suggest that the surfactin-mediated inhibition of breast cancer cell invasion and MMP-9 expression involves the suppression of the NF-κB, AP-1, phosphatidylinositol 3-kinase (PI-3K)/Akt and the ERK signaling pathways. Thus surfactin may have potential value in therapeutic strategies for the treatment of breast cancer metastasis.

/pdf/surfactin-suppresses-tpa-induced-breast-cancer-cell-invasion-ilu3mglv12.pdf

Sang-Joon Lee

Papers

Aerobic Denitrification of Pseudomonas putida AD-21 at Different C/N Ratios

Isolation, identification, and algicidal activity of marine bacteria against Cochlodinium polykrikoides

Surfactin suppresses TPA-induced breast cancer cell invasion through the inhibition of MMP-9 expression.

Achyranthes japonica exhibits anti-inflammatory effect via NF-κB suppression and HO-1 induction in macrophages.

Involvement of PKA and HO-1 signaling in anti-inflammatory effects of surfactin in BV-2 microglial cells.