Laboratory-scale production of acetoin plus diacetyl by Enterobacter cloacae ATCC 27613

Conditions for the laboratory-scale production of acetoin plus diacetyl by Enterobacter Cloacae ATCC 27613 were studied. Thirty-five g acetoin plus diacetyl/50 g sucrose were obtained when fermentation was carried out in 2. 5 liter medium containing 12.5 g peptone and 12. 5 g yeast extract, at pH 7.0, in a 5 liter conical flask on a shaker (240rpm) at 28–30°C for 48 hr. Recovery of pure diacetyl was 85% of the total plus diacetyl.     

BTK-2, a new inhibitor of the Kv1.1 potassium channel purified from Indian scorpion Buthus tamulus

A novel inhibitor of voltage-gated potassium channel was isolated and purified to homogeneity from the venom of the red scorpion Buthus tamulus. The primary sequence of this toxin, named BTK-2, as determined by peptide sequencing shows that it has 32 amino acid residues with six conserved cysteines. The molecular weight of the toxin was found to be 3452 Da. It was found to block the human potassium channel hKv1.1 (IC(50)=4.6 microM). BTK-2 shows 40-70% sequence similarity to the family of the short-chain toxins that specifically block potassium channels. Multiple sequence alignment helps to categorize the toxin in the ninth subfamily of the K+ channel blockers. The modeled structure of BTK-2 shows an alpha/beta scaffold similar to those of the other short scorpion toxins. Comparative analysis of the structure with those of the other toxins helps to identify the possible structure-function relationship that leads to the difference in the specificity of BTK-2 from that of the other scorpion toxins. The toxin can also be used to study the assembly of the hKv1.1 channel.     

Assessment of genetic fidelity of micropropagated <Emphasis Type="Italic">Swertia chirayita</Emphasis> plantlets by ISSR marker assay

Inter simple sequence repeat (ISSR) marker assay was employed to validate the genetic fidelity of Swertia chirayita plantlets multiplied in vitro by axillary multiplication upto forty-two passages. Sixteen ISSR primers generated a total of 102 amplicons among the tissue-cultured plants. Forty-eight amplicons were amplified in the outlier (a Swertia species). The outlier (negative control) was employed to rule out the possibility that the invariant fingerprint was due to chance alone and that the ISSR technique employed was not discriminatory enough to detect the off-types. A homogenous amplification profile was observed for all the micropropagated plants. The results confirmed the clonal fidelity of the tissue culture-raised S. chirayita plantlets and corroborated the fact that axillary multiplication is the safest mode for multiplication of true to type plants.     

Nitric oxide blocks cellular heme insertion into a broad range of heme proteins

Although the insertion of heme into proteins enables their function in bioenergetics, metabolism, and signaling, the mechanisms and regulation of this process are not fully understood. We developed a means to study cellular heme insertion into apo-protein targets over a 3-h period and then investigated how nitric oxide (NO) released from a chemical donor (NOC-18) might influence heme (protoporphyrin IX) insertion into seven targets that present a range of protein structures, heme ligation states, and functions (three NO synthases, two cytochrome P450's, catalase, and hemoglobin). NO blocked cellular heme insertion into all seven apo-protein targets. The inhibition occurred at relatively low (nM/min) fluxes of NO, was reversible, and did not involve changes in intracellular heme levels, activation of guanylate cyclase, or inhibition of mitochondrial ATP production. These aspects and the range of protein targets suggest that NO can act as a global inhibitor of heme insertion, possibly by inhibiting a common step in the process.     

Ascertaining clonal fidelity of micropropagated plants of Dendrocalamus hamiltonii Nees et Arn. ex Munro using molecular markers

Dendrocalamus hamiltonii is a giant, evergreen, clumping, multipurpose bamboo with strong culms which are mainly used for construction, handicrafts and fuel. The tender shoots are also used as food. Overexploitation of existing natural stocks coupled with harvesting of culms before seed formation, a long flowering cycle, irregular and poor seed production, short seed viability, seed sterility, limited availability of offsets and rhizomes and seasonal dependence are some of the major bottlenecks in conventional propagation of this species. Therefore, alternative methods like micropropagation can fill the gap in demand and supply of true-to-type planting material. Recently, our micropropagation protocol for rapid multiplication of D. hamiltonii through axillary bud proliferation using nodal explants from mature culms was standardized, and more than 3,000 plants were transferred to the field. However, somaclonal variations are known to appear in the in vitro-derived clones due to culture-induced stresses. Therefore, the present investigation was conducted to ascertain the effect of the length of in vitro culture age on clonal fidelity of regenerated plants using random amplified polymorphic DNA (RAPD), inter-simple sequence repeat (ISSR), amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers. The genomic DNA samples (i.e. mother plant, in vitro-raised shoots from the 3rd to 30th passage, and in vitro-raised plants transferred to the field) were subjected to PCR amplification using 90 primer combinations (25 each of RAPD, ISSR and SSR, and 15 AFLP primer combinations) of which 76 (23 RAPD, 24 ISSR, 21 SSR and 8 AFLP) markers showed amplified DNA fragments. The 23 RAPD primers produced 162 distinct amplified DNA fragments from 2 (OPE-5) to 16 (OPE-16) fragments per primer, while 24 ISSR primers produced 181 distinct amplified DNA fragments with an average of 7.5 fragments per primer. The number of bands generated by SSR primers varied from 3 (RM-7 and RM-240) to 14 (RM-44), and the eight combinations of AFLP primers produced 369 distinct and scorable amplified DNA fragments with an average of 46.1 fragments per primer. Appearance of monomorphic bands with all the tested primer combinations confirmed the true-to-type nature of the in vitro clones of D. hamiltonii and hence the suitability of the developed micropropagation protocol for commercial-scale plant production.     

Combination of sulfamethoxazole and selenium in anticancer therapy: a novel approach

Sulfonamides have been reported to possess substantial antitumor activity as they act as carbonic anhydrase inhibitors. In addition, selenium appears to have a protective effect at various stages of cancer due to its antioxidant property, enhanced carcinogen detoxification, inhibition of cell invasion, and by inhibiting angiogenesis. Here, in the present study we aimed to evaluate and synergize the cytotoxic activity of sulfonamide and selenium (SM+SE) as effective therapy in the treatment of DENA-induced HCC. Hepatocarcinogeneis was induced by a single intraperitoneal injection of diethylnitrosamine (DENA) (200 mg/kg) in phosphate buffer. 30 Male Wistar rats used in this study were divided randomly into five equal groups (n = 6). DENA-administered animals showed significant alteration (p < 0.001) in liver-specific enzymes—glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), alkaline phosphatase (ALP), and Alpha fetoproteins (AFP), and also induced severe histopathological changes in the hepatic tissues. Interestingly, treatment with (SE+SE) (SM 30 mg/kg + SE 3 mg/kg) significantly reduced (P < 0.001, P < 0.001, P < 0.001, P < 0.001) the elevated AFP, SGOT, SGPT, and ALP levels, respectively, suggesting that combination therapy of SM+SE has a potential to treat DENA-induced liver damage.