Pyrrolnitrin is a commonly used and clinically effective treatment for fungal infections and provides the structural basis for the more widely used fludioxinil. The pyrrolnitrin biosynthetic pathway consists of four chemical steps, the second of which is the rearrangement of 7-chloro-tryptophan by the enzyme PrnB, a reaction that is so far unprecedented in biochemistry. When expressed in Pseudo...

Spatially targeted optical microproteomics (STOMP) is a novel proteomics technique for interrogating micron-scale regions of interest (ROIs) in mammalian tissue, with no requirement for genetic manipulation. Methanol or formalin-fixed specimens are stained with fluorescent dyes or antibodies to visualize ROIs, then soaked in solutions containing the photo-tag: 4-benzoylbenzyl-glycyl-hexahistidi...

The mutL gene product is part of the dam-directed mismatch repair system of Escherichia coli but has no known enzymatic function. It forms a complex on heteroduplex DNA with the mismatch recognition MutS protein and with MutH, which has latent endonuclease activity. An N-terminal hexahistidine-tagged MutL was constructed which was active in vivo. As a first stop to determine the functional doma...

Unlike other characterized phages, the lytic coliphage N4 must inject the 360-kDa virion RNA polymerase (vRNAP), in addition to its 72-kbp genome, into the host for successful infection. The process of adsorption to the host sets up and elicits the necessary conformational changes in the virion to allow genome and vRNAP injection. Infection of suppressor and nonsuppressor strains, Escherichia c...

We previously showed that a fungal protein, p15, induces neurite outgrowth and differentiation of rat pheochromocytoma PC12 cells. We report here the identification and characterization of a protein similar to p15, found in Streptomyces coelicolor A3(2). This hypothetical protein, tentatively named Scp15, has significant similarity with p15, including conserved positions of four cysteine residu...

Fluorescent indicators that allow real-time imaging of Zn(II) in living cells are invaluable tools for understanding Zn(II) homeostasis. Genetically encoded sensors based on fluorescence resonance energy transfer between fluorescent protein domains have important advantages over synthetic probes. We discovered that hexahistidine tags have a strong tendency to dimerize upon binding of Zn(II) in ...

The patS gene encodes a small peptide that is required for normal heterocyst pattern formation in the cyanobacterium Anabaena sp. strain PCC 7120. PatS is proposed to control the heterocyst pattern by lateral inhibition. patS minigenes were constructed and expressed by different developmentally regulated promoters to gain further insight into PatS signaling. patS minigenes patS4 to patS8 encode...

In this paper the multivalent binding of hexahistidine (His6)-tagged proteins to beta-cyclodextrin (beta-CD) self-assembled monolayers (SAMs) by using the nickel(II) complex of a hetero-divalent orthogonal adamantyl nitrilotriacetate linker (4) is described. Nonspecific interactions were suppressed by using monovalent adamantyl-hexa(ethylene glycol) derivative 3. With the mono-His6-tagged malto...

Trichuriasis is a disease of poverty for which excretory and secretory (ES) products that induce the protective immunity are being investigated as candidate vaccines antigens. In this study, ES products of T. muris and immune sera were produced. The immune sera recognized more than 20 proteins on a 2D-gel of ES products of T. muris adult worms. Tm16 was one of the proteins identified by mass sp...

A naïve (unimmunized) human semisynthetic phage display library was employed to isolate recombinant antibody fragments against the cyanobacterial hepatotoxin microcystin-LR. Selected antibody scFv genes were cloned into a soluble expression vector and expressed in Escherichia coli for characterization against purified microcystin-LR by competition enzyme-linked immunosorbent assay (ELISA). The ...