When we founded this journal back in 2008, chemical biology was still an emerging discipline that had not yet made an impact in the publishing landscape with only a few journals and many of the other journals keeping close to their core disciplines. However, nearly a decade onwards, most journals welcome multidisciplinary manuscripts, although only a few “chemical biology” focused journals exist. Journal of Chemical Biology belongs to the latter category, publishing multidisciplinary manuscripts that cover a wide range of topics with a particular emphasis on the innovation within the physical sciences, but also informing the chemical biology community through its bulletin of interesting conferences, books, and news. Since its inception, over 150 manuscripts have been published in the Journal of Chemical Biology attracting over 1400 citations (without self-citations; web of science search on all databases) demonstrating the high impact of the work published.However, the developments in the publishing landscape made it clear that the interests of our authors are best served by aligning ourselves with the ChemCentral Journal (https://ccj.springeropen.com), an open access publication by Springer that is listed in many indexing services including the Science Citation Index (current Impact factor: 2.442). The Journal of Chemical Biology will cease publishing, with this issue being the last one, but will continue to serve the chemical biology community in the newly formed chemical biology section of the ChemCentral Journal. In order to ensure a smooth transition and translation of the chemical biology culture and spirit, we will serve as editors for this section and would invite all potential authors to consider submitting their manuscripts to ChemCentral Journal/chemical biology section from now on.We wish to thank the chemical biology community for all contributions including items for the bulletin. In particular, we would like to thank our bulletin editor Colin Rosser, who managed that part of our journal, as well as all our current and past editors, authors, and referees, who all made sure that we published high-quality manuscripts over the years.Banafshe Larijani and Rudiger WoscholskiEditors-in-Chief

In this paper evidence is presented that the fatty acid component of an inositide substrate affects the kinetic parameters of the lipid phosphatase Salmonella Outer Protein B (SopB). A succinct route was used to prepare the naturally occurring enantiomer of phosphatidylinositol 4-phosphate (PI-4-P) with saturated, as well as singly, triply and quadruply unsaturated, fatty acid esters, in four stages: (1) The enantiomers of 2,3:5,6-O-dicyclohexylidene-myo-inositol were resolved by crystallisation of their di(acetylmandelate) diastereoisomers. (2) The resulting diol was phosphorylated regio-selectively exclusively on the 1-O using the new reagent tri(2-cyanoethyl)phosphite. (3) With the 4-OH still unprotected, the glyceride was coupled using phosphate tri-ester methodology. (4) A final phosphorylation of the 4-O, followed by global deprotection under basic then acidic conditions, provided PI-4-P bearing a range of sn-1-stearoyl, sn-2-stearoyl, -oleoyl, -γ-linolenoyl and arachidonoyl, glycerides. Enzymological studies showed that the introduction of cis-unsaturated bonds has a measurable influence on the activity (relative Vmax) of SopB. Mono-unsaturated PI-4-P exhibited a five-fold higher activity, with a two-fold higher KM, over the saturated substrate, when presented in DOPC vesicles. Poly-unsaturated PI-4-P showed little further change with respect to the singly unsaturated species. This result, coupled with our previous report that saturated PI-4-P has much higher stored curvature elastic stress than PI, supports the hypothesis that the activity of inositide phosphatase SopB has a physical role in vivo.

Arylstibonates structurally resemble phosphotyrosine side chains in proteins and here we addressed the ability of such compounds to act as inhibitors of a panel of mammalian tyrosine and dual-specificity phosphatases. Two arylstibonates both possessing a carboxylate side chain were identified as potent inhibitors of the protein tyrosine phosphatase PTP-ß. In addition, they inhibited the dual-specificity, cell cycle regulatory phosphatases Cdc25a and Cdc25b with sub-micromolar potency. However, the Cdc25c phosphatase was not affected demonstrating that arylstibonates may be viable leads from which to develop isoform specific Cdc25 inhibitors.

Inositol phospholipids have emerged as important key players in a wide variety of cellular functions. Among the seven existing inositol phospholipids, phosphatidylinositol (4,5)-bisphosphate (PI(4,5)P2) has attracted much attention in recent years due to its important role in numerous cellular signaling events and regulations, which in turn impact several human diseases. This particular lipid is recognized in the cell by specific lipid binding domains, such as the Pleckstrin-homology (PH) domain, which is also employed as a tool to monitor this important lipid. Here, we describe the synthesis and biological characterization of a small molecule that mimics the PH domain as judged by its ability to bind specifically to only PI(4,5)P2 and effectively compete with the PH domain in vitro and in a cellular environment. The binding constant of this small molecule PH domain mimetic (PHDM) was determined to be 17.6 ± 10.1 μM, similar in potency to the PH domain. Using NIH 3T3 mouse fibroblast cells we demonstrated that this compound is cell-permeable and able to modulate PI(4,5)P2-dependent effects in a cellular environment such as the endocytosis of the transferrin receptor, loss of mitochondria, as well as stress fiber formation. This highly PI(4,5)P2-specific chemical mimetic of a PH domain not only is a powerful research tool but might also be a lead compound in future drug developments targeting PI(4,5)P2-dependent diseases such as Lowe syndrome.

PTEN (phosphatase and tensin homologue deleted on chromosome 10) is well known as a tumour suppressor. It’s PI(3,4,5)P3 lipid phosphatase activity is an important counteracting mechanism in PI 3-kinase (phosphoinositide 3-kinase) signalling. Furthermore, PTEN lies upstream of Akt kinase, a key enzyme in insulin signalling regulating glucose uptake and cell growth. Therefore, PTEN has recently gained attention as a valuable drug target for the treatment of diabetes, stroke, cardiac infarct and fertility. This review summarizes the use of small molecules as PTEN inhibitors. Currently available methodologies and techniques for accessing PTEN inhibition in vitro and in cellulo will be discussed.

In this paper evidence is presented that the fatty acid component of an inositide substrate affects the kinetic parameters of the lipid phosphatase Salmonella Outer Protein B (SopB). A succinct route was used to prepare the naturally occurring enantiomer of phosphatidylinositol 4-phosphate (PI-4-P) with saturated, as well as singly, triply and quadruply unsaturated, fatty acid esters, in four stages: (1) The enantiomers of 2,3:5,6-O-dicyclohexylidene-myo-inositol were resolved by crystallisation of their di(acetylmandelate) diastereoisomers. (2) The resulting diol was phosphorylated regio-selectively exclusively on the 1-O using the new reagent tri(2-cyanoethyl)phosphite. (3) With the 4-OH still unprotected, the glyceride was coupled using phosphate tri-ester methodology. (4) A final phosphorylation of the 4-O, followed by global deprotection under basic then acidic conditions, provided PI-4-P bearing a range of sn-1-stearoyl, sn-2-stearoyl, -oleoyl, -γ-linolenoyl and arachidonoyl, glycerides. Enzymological studies showed that the introduction of cis-unsaturated bonds has a measurable influence on the activity (relative Vmax) of SopB. Mono-unsaturated PI-4-P exhibited a five-fold higher activity, with a two-fold higher KM, over the saturated substrate, when presented in DOPC vesicles. Poly-unsaturated PI-4-P showed little further change with respect to the singly unsaturated species. This result, coupled with our previous report that saturated PI-4-P has much higher stored curvature elastic stress than PI, supports the hypothesis that the activity of inositide phosphatase SopB has a physical role in vivo.