Expression of the Clifednamide Biosynthetic Pathway in Generates 27,28--Derivatives.

Polycyclic tetramate macrolactams (PoTeMs) are a group of hybrid PK-NRP natural products having a variable set of carbocyclic rings, a conserved assembly pathway, and diverse bioactivities. We report here the identification of seven new PoTeMs, clifednamides D-J (-), along with the known clifednamides A () and B () through rational pathway refactoring and heterologous expression. Remarkably, clifednamides D (), G (), and H () feature an unprecedented 27,28- skeleton.

Structural and molecular basis for the novel catalytic mechanism and evolution of DddP, an abundant peptidase-like bacterial Dimethylsulfoniopropionate lyase: a new enzyme from an old fold.

The microbial cleavage of dimethylsulfoniopropionate (DMSP) generates volatile dimethyl sulfide (DMS) and is an important step in global sulfur and carbon cycles. DddP is a DMSP lyase in marine bacteria, and the deduced dddP gene product is abundant in marine metagenomic data sets. However, DddP belongs to the M24 peptidase family according to sequence alignment.

Identification and catalytic characterization of a nonribosomal peptide synthetase-like (NRPS-like) enzyme involved in the biosynthesis of echosides from Streptomyces sp. LZ35.

Echosides, isolated from Streptomyces sp. LZ35, represent a class of para-terphenyl natural products that display DNA topoisomerase I and IIα inhibitory activities. By analyzing the genome draft of strain LZ35, the ech gene cluster was identified to be responsible for the biosynthesis of echosides, which was further confirmed by gene disruption and HPLC analysis.

Crystallization and preliminary x-ray diffraction analysis of a novel mannose-binding lectin with antiretroviral properties from Polygonatum cyrtonema hua.

A novel antiretroviral protein Polygonatum cyrtonema lectin (PCL) belonging to the monocot mannose-binding lectin (MMBL) superfamily has been crystallized using hanging-drop vapor-diffusion method. The crystals diffract to 2.0 A resolution and belong to space group P2(1), with unit-cell parameters of a=39.

Crystal structure of Mabinlin II: a novel structural type of sweet proteins and the main structural basis for its sweetness.

The crystal structure of a sweet protein Mabinlin II (Mab II) isolated from the mature seeds of Capparis masaikai Levl. grown in Southern China has been determined at 1.7A resolution by the SIRAS method.

A periplasmic glutamate/aspartate binding protein from Shigella flexneri: Gene cloning, over-expression, purification and preliminary crystallographic studies of the recombinant protein.

Periplasmic substrate binding proteins (PSBPs) are essential components of the bacterial periplasmic transport system, which transports a wide variety of nutrients from the periplasmic space to the cytoplasm. The glutamate/aspartate binding protein SfGlu/AspBP is a unique PSBP consisting of 279 amino acid residues. The SfGlu/AspBP gene was cloned, over-expressed, and purified by immobilized metal ion affinity chromatography and size-exclusion chromatography.

Crystallization and preliminary X-ray analysis of the highly thermostable sweet protein Mabinlin II.

Mabinlin II is a thermostable sweet protein isolated from the mature seeds of Capparis masaikai Levl. grown in the subtropical region of the South of China. The Mabinlin II has been crystallized and diffraction data were collected to 1.

Expression, purification and crystallization of a human protein SH3BGRL at atomic resolution.

The protein SH3BGRL, containing both SH3-binding and Homer EVH1-binding motifs, has been crystallized using the hanging-drop vapour-diffusion method. The crystals diffract to 0.88 A resolution and belong to space group P2(1)2(1)2(1), with unit-cell parameters a = 28.

Purification and preliminary crystallographic studies of CutC, a novel copper homeostasis protein from Shigella flexneri.

CutC is a novel copper homeostasis protein containing 248 amino acids. Here we report the cloning, expression, purification, crystallization and preliminary X-ray crystallographic studies of CutC from Shigella flexneri 2a. Purification of CutC and its selenomethionine (SeMet) derivate were done using immobilized metal ion affinity chromatography, size-exclusion and ion-exchange chromatography.

Optimizing protein crystal growth through dynamic seeding.

A dynamic seeding method that is different from the conventional method of seeding drops that have been equilibrated is described. The method basically consists of two steps. Firstly, microseeding was used in association with adjustment of the seeding-drop components, including buffer, additive and concentrations of the precipitants and protein, in order to screen suitable seeding conditions under which microseeds are seeded into a new non-equilibrated drop as the dynamic macroseed drop for the following step.