Frequency distribution of space groups in soluble and membrane proteins and their complexes.

The space-group frequency distributions for two types of proteins and their complexes are explored. Based on the incremental availability of data in the Protein Data Bank, an analytical assessment shows a preferential distribution of three space groups, i.e. P212121 > P1211 > C121, in soluble and membrane proteins as well as in their complexes. In membrane proteins, the order of the three space groups is P212121 > C121 > P1211. The distribution of these space groups also shows the same pattern whether a protein crystallizes with a monomer or an oligomer in the asymmetric unit. The results also indicate that the sizes of the two entities in the structures of soluble proteins crystallized as complexes do not influence the frequency distribution of space groups. In general, it can be concluded that the space-group frequency distribution is homogenous across different types of proteins and their complexes.

Cellular network based drug monitoring.

Pharmacovigilance is a resourceful process for monitoring adverse drug reactions. The lack of resources in developing countries makes it difficult to execute pharamcovigilance programs on a large scale. Therefore, the cellular technology based network, which has widespread access in the developing world, may be used as an inexpensive means of monitoring.

Prokaryotic and eukaryotic integral membrane proteins have similar architecture.

Integral membrane proteins constitute a major constituent of lipid bilayer both in prokaryotes and eukaryotes. The statistical analysis was carried out to determine the bias in amino acid distribution between prokaryotic and eukaryotic integral membrane proteins (pIntMPs and eIntMPs). Our results indicate that both pIntMPs and eIntMPs demonstrate the striking similarity in amino acid distribution in their transmembrane and extramembranous region. pIntMPs have relatively greater functional importance for Gly and Asn in comparison to eIntMPs.

Helicase: mystery of progression.

Helicases mode of unwinding the nucleic acids and translocation along single stranded nucleic acids is still a subject of great curiosity. Based on the energy transduction and electrophilic interactions, we present a model to explain the mode of action of active helicases. This model considers that both strand separation as well as translocation is active processes fueled by NTP hydrolysis. The model proposes that the translocation appears to involve creeping of helicase over the ssNA lattice rather than inchworm movement.

Structure of a non-camelized human M12-V(H) domain at 1.5A resolution.

A non-camelized human V(H) domain has been crystallized through limited in vitro proteolysis of scFvM12 antibody fragment. The protease addition results in the complete degradation of the M12-V(L) domain, linker, and purification tags. The structure solved up to 1.5A resolution having good stereochemistry with a R(cryst) factor of 15.8% and R(free) factor of 19.7%. Dihedral angle values comparison of the first and the second complementarity-determining region (CDR) of M12-V(H) domain with an average values show a significant deviation; therefore, M12-V(H) domain structure indicates either the existence of a new canonical subclass or a link among the subclasses of canonical main-chain conformation in V(H)3 family. The presence of uncommon hydrogen bond between Ser-H50 and Tyr-H97 has pulling effect on CDR-H3 loop. The interface area buried by CDR-H3 loop indicates the partial coverage of the hydrophobic V(L)-V(H) interface. The isolated M12-V(H) domain was found soluble up to 0.35 mM. This result would be helpful in structure based designing of an isolated human single domain antibody fragments for biotechnological and pharmaceutical applications such as cancer.

Preliminary X-ray analysis of a human V(H) fragment at 1.8 A resolution.

Small antibody fragments are more useful than full-size antibodies for achieving efficient biodistribution. As a first step towards the design of a clinically desirable antibody fragment, the crystallization of a human V(H) fragment has been achieved. The fragment was derived from the single-chain antibody scFvM12, which recognizes a cancer-specific hypoglycosylated form of mucin. The V(H) fragment was obtained by in-drop digestion of the scFvM12 with a low concentration of the broad-spectrum protease subtilisin Carlsberg. The crystal belongs to the monoclinic space group C2. The crystal diffracted to 1.8 A resolution when analysed at 100 K using a rotating-anode X-ray generator.

Effect of seed culture on solid-state bioconversion of wheat straw by Phanerochaete chrysosporium for animal feed production.

The solid-state bioconversion of wheat straw by Phanerochaete chrysosporium for the production of animal feed was studied. This study was performed based on a central composite experimental design. The conditions of the seed culture most suitable for rapid induction of the ligninolytic activity of the fungus, when the seed culture is subsequently used for solid-state bioconversion of wheat straw, were determined. When the seed culture with an initial pH of 5.8 was grown under agitated conditions at 130 rpm in baffled flasks at 38 degrees C, it was predicted to give lignin degradation of 19.5% and cellulose degradation of 17.8%. A time profile study of the solid-state bioconversion of wheat straw indicated that the highest lignin and lowest cellulose degradation levels occurred on the sixth day of cultivation. The desirability coefficient for this process also passed through a maximum of 0.705 on the sixth day.