The first zoeal stage of the genus Cronius (Brachyura, Portunidae) from the Brazilian coast, hatched in a laboratory

This study describes the first zoeal stage of Cronius ruberand Cronius tumidulus. The zoeae can be distinguished usingthe setation of the cephalic appendages and the lateral processon the abdominal somite.     

Theoretical study of the effects of substituents (F,Cl, Br,CH<Subscript>3</Subscript>, and CN) on the aromaticity of borazine

This paper presents a theoretical study of the effects of substituents (F, Cl, Br, CH₃, and CN) on the aromaticity of borazine (B₃N₃H₆), using density functional theory (DFT) and the Hartree-Fock (HF) method. The calculations to optimize the geometries, structural properties, and vibrational frequencies were performed using the same 6–311G(d,p) and 6–311++G(d,p) basis sets, comparing the methods with experimental results. In the analysis of the NICS_ZZ values, it was found that that replacing the hydrogen atoms by halogen atoms (F, Cl, and Br) and CH₃ reduced the aromaticity of the borazine molecule, while use of the CN group resulted in NICS_ZZ values (0.9–2.0 Å) very close to those of borazine, presenting the following order of increasing aromaticity: B₃N₃H₃-(Br)₃?<?B₃N₃H₃-(Cl)₃?<?B₃N₃H₃-(F)₃?<?B₃N₃H₃-(CH₃)₃?<?B₃N₃H₆ ~ B₃N₃H₃-(CN)₃. All the spectra of the compounds showed only the presence of transition peaks distant from the UV region, reflecting the large energy difference between the HOMO and LUMO orbitals. After the substitution of the borazine ring, all the compounds presented an intensification of the spectrum, with a shift of the maximum absorbance toward red, indicative of a bathochromic effect. There was a direct inverse relation between the energy gap and the maximum wavelength of the compounds.     

Predicting synthetic rescues in metabolic networks

An important goal of medical research is to develop methods to recover the loss of cellular function due to mutations and other defects. Many approaches based on gene therapy aim to repair the defective gene or to insert genes with compensatory function. Here, we propose an alternative, network‐based strategy that aims to restore biological function by forcing the cell to either bypass the functions affected by the defective gene, or to compensate for the lost function. Focusing on the metabolism of single‐cell organisms, we computationally study mutants that lack an essential enzyme, and thus are unable to grow or have a significantly reduced growth rate. We show that several of these mutants can be turned into viable organisms through additional gene deletions that restore their growth rate. In a rather counterintuitive fashion, this is achieved via additional damage to the metabolic network. Using flux balance‐based approaches, we identify a number of synthetically viable gene pairs, in which the removal of one enzyme‐encoding gene results in a non‐viable phenotype, while the deletion of a second enzyme‐encoding gene rescues the organism. The systematic network‐based identification of compensatory rescue effects may open new avenues for genetic interventions.     

Soybean peroxidase immobilized on δ-FeOOH as new magnetically recyclable biocatalyst for removal of ferulic acid

Bioprocess and Biosystems Engineering - A significant enhancement in the catalytic performance due to enzymes immobilization is a great way to enhance the economics of biocatalytic processes. The...     

EHD2 and the novel EH domain binding protein EHBP1 couple endocytosis to the actin cytoskeleton

Here we identified two novel proteins denoted EH domain protein 2 (EHD2) and EHD2-binding protein 1 (EHBP1) that link clathrin-mediated endocytosis to the actin cytoskeleton. EHD2 contains an N-terminal P-loop and a C-terminal EH domain that interacts with NPF repeats in EHBP1. Disruption of EHD2 or EHBP1 function by small interfering RNA-mediated gene silencing inhibits endocytosis of transferrin into EEA1-positive endosomes as well as GLUT4 endocytosis into cultured adipocytes. EHD2 localizes with cortical actin filaments, whereas EHBP1 contains a putative actin-binding calponin homology domain. High expression of EHD2 or EHBP1 in intact cells mediates extensive actin reorganization. Thus EHD2 appears to connect endocytosis to the actin cytoskeleton through interactions of its N-terminal domain with membranes and its C-terminal EH domain with the novel EHBP1 protein.     

Temporal-spatial distribution of the hermit crab Loxopagurus loxochelis (Decapoda: Diogenidae) from Ubatuba Bay, São Paulo State, Brazil

The present work was conducted to determine the distribution of Loxopagurus loxochelis collected monthly, over a period of one year. in Ubatuba Bay (from September/95 to August/96). A total of 179 specimens were collected (138 males, 30 females and 11 ovigerous females). The greatest depth, predominance of very fine sand and highest mean value of organic matter contents of sediment, in combination with the low temperatures registered in winter (July and August), determined the presence of L. loxochelis in the subarea located at the Ubatuba Bay mouth, exposed to the open sea with high water current energy, important because this position insures that spawned larvae will enter into the oceanic circulation.     

Biodiversity of brachyuran crabs (Crustacea: Decapoda) from non-consolidated sublittoral bottom on the northern coast of São Paulo State, Brazil

The brachyuran community of the coast of São Paulo State is represented by about 188 species of crabs inhabiting different kinds of coastal marine environments. The biodiversity of brachyurans found on non-consolidated sublittoral bottom was investigated. The Ubatuba region (Ubatumirim, Ubatuba and Mar Virado bays, Couves and Mar Virado Islands, offshore region) was sampled for 3 years (1998–2000), at depths of 2–40 m. All sampling was performed using a fishing boat equipped with two double-rig nets. We collected 79 brachyuran species representing 9 superfamilies (4 Dromioidea, 1 Homoloidea, 2 Calappoidea, 5 Leucosioidea, 20 Majoidea, 7 Parthenopoidea, 17 Portunoidea, 18 Xanthoidea, and 5 Pinnotheroidea) and 41 genera. Ubatuba bay showed the greatest species richness with 50 species, followed by Ubatumirim with 45 and Mar Virado with 29. The number of species collected represents about 57% of the known species of crabs already reported for the shore of São Paulo State. It is worth noticing that this percentage is restricted only to non-consolidated sublittoral bottom. This fact indicates a great biodiversity of the habitat in this studied region, probably one to the diversity of habitat types present in the bays.     

Mycoparasitism studies of Trichoderma harzianum strains against Rhizoctonia solani: evaluation of coiling and hydrolytic enzyme production

The genus Trichoderma is a potential biocontrol agent against several phytopathogenic fungi. One parameter for its successful use is an efficient coiling process followed by a substantial production of hydrolytic enzymes. The interaction between fifteen isolates of Trichoderma harzianum and the soil-borne plant pathogen, Rhizoctonia solani, was studied by light microscopy and transmission electron microscopy (TEM). Macroscopic observations of fungal growth in dual cultures revealed that growth inhibition of the pathogen occurred soon after contact with the antagonist. All T. harzianum isolates tested exhibited coiling around the hyphae of R. solani. The strains ALL23, ALL40, ALL41, ALL43 and ALL49 did not differ in coiling frequency and gave equal coiling performances. No correlation between coiling frequency and the production of cell wall-degrading chitinases, N-acetyl-β-d-glucosaminidase and β-1,3-glucanases, was found.     

Ecological distribution of the shrimp Pleoticus muelleri (Bate, 1888) (Decapoda: Penaeoidea) in southeastern Brazil

The abundance and ecological distribution of the shrimp Pleoticus muelleri as a function of certain environmental factors were investigated from January 1998 through December 1999 in the region of Ubatuba, São Paulo, Brazil. The collections were made monthly in the bays of Ubatumirim (UBM), Ubatuba (UBA) and Mar Virado (MV). Each bay was divided into six sampling transects, four transects parallel to the shoreline and two near the rocky shores on the opposite side. We employed a commercial shrimp boat equipped with two double-rig nets. A total of 6252 shrimp were collected, including 3321 from MV, 1467 from UBM, and 1464 from UBA. Most of the shrimp were caught in the deeper, higher-salinity areas. The high abundance of P. muelleri observed in the southern part of the region studied was related to a sediments with a higher percentage of silt and clay. The numbers of P. muelleri were positively correlated with periods of cooler temperatures. Thus, temperature and the type of sediment were determinant factors in the distribution of P. muelleri in this region.     

A Novel Phosphorylated Lipid Counteracts Activation of the Renal Plasma Membrane (Ca2+ + Mg2+)ATPase by Endogenous Phosphatidylinositol-4-Phosphate

The plasma membrane (Ca²⁺ + Mg²⁺)ATPase is activated by acidic phospholipids in reconstituted systems. In this report it is shown that reversible phosphorylation of endogenous phosphatidylinositol regulates the renal plasma membrane (Ca²⁺ + Mg²⁺)ATPase, and that a novel phosphorylated lipid that can be isolated from the same membrane strongly counteracts the stimulatory effect of phosphatidylinositol-4-phosphate.