Identification of a Novel Anti-cancer Protein, FIP-bbo, from Botryobasidium botryosum and Protein Structure Analysis using Molecular Dynamic Simulation.

Fungal immunoregulatory proteins (FIP) are effective small molecule proteins with broad-spectrum immunomodulatory and anti-cancer activities and can be potential agents for the development of clinical drugs and health food additives. In this study, a new member of FIP named FIP-bbo was obtained through Botryobasidium botryosum genome mining. FIP-bbo has the typical characteristics of FIP but is genetically distant from other FIPs. Recombinant FIP-bbo (rFIP-bbo) was produced in an optimized E. coli expression system, and the pure protein was isolated using a Ni-NTA column. Antineoplastic experiments suggested that FIP-bbo is similar to LZ-8 in inhibiting various cancer cells (Hela, Spac-1, and A549) at lower concentrations, but it is not as potent as LZ-8. The molecular mechanism by which FIP-bbo, FIP-fve, and LZ-8 are cytotoxic to cancer cells has been discussed based on molecular dynamics simulation. Point mutations that may improve the thermal stability of FIP-fve and FIP-bbo were predicted. These results not only present a new candidate protein for the development of anticancer adjuvants, but also provide an approach for designing FIPs with high anticancer activity.

Computational Insights into the Molecular Mechanism of the High Immunomodulatory Activity of LZ-8 Protein Isolated from the Lingzhi or Reishi Medicinal Mushroom Ganoderma lucidum (Agaricomycetes).

Ling zhi-8 (LZ-8) is the first fungal immunomodulatory protein (FIP) isolated from the lingzhi or reishi medicinal mushroom, Ganoderma lucidum. LZ-8 effectively induces interleukin 2 expression and secretion by forming a stable homodimer, and it is regarded as a good candidate to become a new therapeutic agent and/or functional food supplement. However, the molecular mechanism by which LZ-8 dimerization influences the regulation of interleukin 2 is not clear. In this study we performed structure-based multiple alignment of LZ-8 and an FIP from Volvariella volvacea, compared the electrostatic potential of their protein surfaces, and developed a model summarizing the unique electrostatic interaction in LZ-8 dimerization. In addition, further electrostatic potential and virtual amino acid mutation analyses suggested that L10, W12, and D45 are the key amino acid residues responsible for the protein's high immunomodulatory activity. These findings may provide useful insights into the design and construction of a new FIP mutant for use in treating and preventing autoimmune diseases.

Comparison and Validation of Putative Pathogenicity-Related Genes Identified by T-DNA Insertional Mutagenesis and Microarray Expression Profiling in Magnaporthe oryzae.

High-throughput technologies of functional genomics such as T-DNA insertional mutagenesis and microarray expression profiling have been employed to identify genes related to pathogenicity in Magnaporthe oryzae. However, validation of the functions of individual genes identified by these high-throughput approaches is laborious. In this study, we compared two published lists of genes putatively related to pathogenicity in M. oryzae identified by T-DNA insertional mutagenesis (comprising 1024 genes) and microarray expression profiling (comprising 236 genes), respectively, and then validated the functions of some overlapped genes between the two lists by knocking them out using the method of target gene replacement. Surprisingly, only 13 genes were overlapped between the two lists, and none of the four genes selected from the overlapped genes exhibited visible phenotypic changes on vegetative growth, asexual reproduction, and infection ability in their knockout mutants. Our results suggest that both of the lists might contain large proportions of unrelated genes to pathogenicity and therefore comparing the two gene lists is hardly helpful for the identification of genes that are more likely to be involved in pathogenicity as we initially expected.

The genome of Pleurotus eryngii provides insights into the mechanisms of wood decay.

Pleurotus eryngii (DC.) Quél. is widely used for bioconverting lignocellulosic byproducts into biofuel and value added products. Sequencing and annotating the genome of a monokaryon strain P. eryngii 183 allows us to gain a better understanding of carbohydrate-active enzymes (CAZymes) and oxidoreductases for degradation of lignocellulose in white-rot fungi. The genomic data provides insights into genomic basis of degradation mechanisms of lignin and cellulose and may pave new avenues for lignocellulose bioconversion.