The coastal marine cyanobacterium Synechococcus sp. PCC 7002 produces three amphiphilic siderophores, synechobactins A‐C, under iron‐limiting growth conditions. The synechobactins are comprised of a citric acid backbone linked to two 1, 3‐diaminopropane units. The terminal amine of one diaminopropane is acetylated and hydroxylated forming one hydroxamate group. The terminal amine of the other diaminopropane is appended to one of a series of fatty acids and N‐hydroxylated on the fatty acid amide forming the second hydroxamate linkage. Synechobactins A‐C differ among themselves in the identity of the fatty acid residue as dodecanoic acid, decanoic acid, or octanoic acid, respectively. They are the first structurally elucidated siderophores from marine cyanobacteria and are related to schizokinen, a previously identified siderophore that lacks amphiphilic character, isolated from other bacteria including freshwater cyanobacteria.

The coastal alpha-proteobacterium Ochrobactrum sp. SP18 produces a suite of three citrate-derived, cell-associated amphiphilic siderophores, ochrobactins A-C. The ochrobactins are composed of a citric acid backbone amide-linked to two lysine residues. Each epsilon-amine of lysine is hydroxylated and acylated forming two hydroxamic acid moieties. One of the acylated appendages of each ochrobactin is (E)-2-decenoic acid. The other acylated appendages for ochrobactins A-C are (E)-2-octenoic acid, octanoic acid and (E)-2-decenoic acid, respectively. The ferric ochrobactin complexes are photoreactive in UV light, producing an oxidized ligand with loss of 46 mass units that can still coordinate Fe(III). The relative partitioning of the apo-ochrobactins, Fe(III) ochrobactins and Fe(III) photoproducts into 1,2-dimyristoyl-sn-glycero-3-phosphocholine vesicles is presented. The ochrobactins are the first example of aerobactin-based siderophores with two fatty acid appendages produced in a suite with varying acyl appendage lengths.

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Although podocyte damage is known to be responsible for the development of minimal-change disease (MCD), the underlying mechanism remains to be elucidated. Previously, using a rat MCD model, we showed that endoplasmic reticulum (ER) stress in the podocytes was associated with the heavy proteinuric state and another group reported that a mammalian target of rapamycin complex 1 (mTORC1) inhibitor protected against proteinuria. In this study, which utilized a rat MCD model, a combination of immunohistochemistry, dual immunofluorescence and confocal microscopy, western blot analysis, and quantitative real-time RT-PCR revealed co-activation of the unfolded protein response (UPR), which was induced by ER stress, and mTORC1 in glomerular podocytes before the onset of proteinuria and downregulation of nephrin at the post-translational level at the onset of proteinuria. Podocyte culture experiments revealed that mTORC1 activation preceded the UPR that was associated with a marked decrease in the energy charge. The mTORC1 inhibitor everolimus completely inhibited proteinuria through a reduction in both mTORC1 and UPR activity and preserved nephrin expression in the glomerular podocytes. In conclusion, mTORC1 activation may perturb the regulatory system of energy metabolism primarily by promoting energy consumption and inducing the UPR, which underlie proteinuria in MCD.

The natural forest in Yanbaru, the northern Although an area in Yanbaru occupied by the US part of the main island of Okinawa (Okinawa Hontô ), Marine Corps has, to date, preserved good natural forest, a new plan to establish seven military helipads is an important area for nature conservation, because it in this area is now being examined. Possible outcomes has a large number of endemic animals and plants. First, we explain the status of the most important of such a development are evaluated. In addition, requests by Japanese biologists for the Defence Facilities endemic animals of Yanbaru, stressing that most of them are endangered and near extinction. Second, we Administration Agency, Japan to consider alternate sites for the helipads are described. show especially high species diversity of trees, insects and mites in the Yanbaru forest. However, the integrity Keywords Endangered species, endemism, Japan, Oki-of the Yanbaru forest is seriously threatened by clearcutting and complete removal of forest undergrowth. nawan forests, species diversity, Yanbaru.

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