High level of divergence of male-reproductive-tract proteins, between Drosophila melanogaster and its sibling species, D. simulans

We compared male-reproductive-tract polypeptides of Drosophila melanogaster and D. simulans by using two-dimensional gel electrophoresis. Approximately 64% of male-reproductive-tract polypeptides were identical between two randomly chosen isofemale lines from these two species, compared with 83% identity for third-instar imaginal wing-disc polypeptides. Qualitatively similar differences were found between reproductive tracts and imaginal discs when D. sechellia was compared with D. melanogaster and with D. simulans. When genic polymorphism was taken into account, approximately 10% of male- reproductive-tract polypeptides were apparently fixed for different alleles between D. melanogaster and D. simulans; this proportion is the same as that found for soluble enzymes by one-dimensional gel electrophoresis. Strikingly, approximately 20% of male-reproductive- tract polypeptides of either D. melanogaster or D. simulans had no detectable homologue in the other species. We propose that proteins of the Drosophila male reproductive tract may have diverged more extensively between species than have other types of proteins and that much of this divergence may involve large changes in levels of polypeptide expression.      

Pre-induction priming of the uterine cervix with oral prostaglandin E2 and a placebo

A double blind study was undertaken to determine the effectiveness or oral prostaglandin E2 as a means of improving the pelvic score prior to induction of labour. 48 patients who were greater than 37 were gestation and who had Bishop scores of less than 6 entered the study. Ten tablets were given on an hourly regime. Of 25 patients in the prostaglandin group, 17 were considered successes (68.0%), whereas of 23 patients who received a placebo, 9 were successes (39.1%). No adverse effects were recorded. Prostaglandin E2 is therefore considered a safe and effective method for priming the unfavourable cervix prior to induction of labour.     

Monoclonal antibodies to rabbit liver cytochrome P-448

Cytochrome P-448 (mol wt 55,000 Daltons) from rabbit liver was purified to a specific content of 16.6 nmol/mg. Mice were immunised with this preparation, their spleens removed and dissociated lymphocytes hybridised with myeloma cells. Four monoclonal antibodies against cytochrome P-448 were raised and partially characterised. All four antibodies interacted with cytochrome P-448 in intact microsomal fractions and selectively immunoadsorbed cytochrome P-448 from solubilised microsomal preparations. One of the antibodies inhibited benzo[a] pyrene hydroxylase activity in a reconstituted system, one had no effect on activity and two increased activity. The possible applications of such antibodies are discussed.     

Molecular cloning of a thermo-alkaliphilic lipase from Bacillus subtilis DR8806: Expression and biochemical characterization

A thermo-alkaliphilic lipase from Bacillus subtilis DR8806 was functionally expressed as an N-terminal 6xHis-tagged recombinant enzyme in Escherichia coli BL21 using pET-28a(+) expression vector. Sequence analysis revealed an open reading frame of 639 bp encoding a 212-amino acid protein containing the well-conserved Ala-His-Ser-Met-Gly motif. One-step purification of the His-tagged recombinant lipase was achieved using Ni-NTA affinity chromatography with a specific activity of 1364 U/mg. The purified enzyme with an apparent molecular mass of 26.8 kDa demonstrated the maximum activity at 70 °C and pH 8.0 for hydrolysis of p-nitrophenylbutyrate as substrate. The enzyme activity was strongly inhibited by divalent ions of heavy metals such as Hg²⁺ and Cu²⁺, while retained over 90% of the original activity in the presence of several reagents including DTNB (5,5′-dithiobis-(2-nitrobenzoic acid)), SDS (sodium dodecyl sulfate), urea, DMF (dimethylformamide), DTT (dithiothreitol), glycerol and Triton X-100. While being considerably stable in organic solvents, imidazolium-based ionic liquids (ILs) had stimulatory effects on the activity of purified lipase. Remarkable stabilization of enzyme at alkaline pH and in ionic liquids as well as its thermostability/thermoactivity are among the most fundamental characteristics which offer great potential for various biotechnological applications including detergent formulation, bioremediation processes and biotransformation in non-aqueous media.     

Alleviation of chromium toxicity in rice seedlings by applying exogenous glutathione

The effect of exogenous reduced glutathione (GSH) on alleviation of hexavalent chromium (Cr⁶⁺) toxicity to rice seedlings and its physiological mechanisms were comprehensively investigated in a series of experiments. Our results showed that growth and nutrient uptake of rice seedlings were dramatically reduced under 100 μM Cr⁶⁺ stress, and the reduction was significantly alleviated by exogenous GSH. Cr⁶⁺ stress also reduced cell viability in root tips and damaged ultrastructure of both chloroplasts and root cells, while the addition of GSH alleviates those negative effects. Cr-induced toxicity and GSH-caused Cr alleviation differed significantly between Cr-tolerant Line 117 (L117) and Cr-sensitive Line 41 (L41). Under Cr⁶⁺ stress, cystine content was increased and GSH content was decreased in rice plants, exogenous GSH, however, mitigated the Cr-toxicity by reversing the Cr-induced changes of the two compounds. The types of Cr-induced secretion of organic acids varied between the genotypes, where reduction in the contents of acetic and lactic acids and tartaric and malic acids were observed in L117 and L41, respectively. The addition of GSH alleviated the reduction of secretion of these organic acids. Exogenous GSH also altered the forms of Cr ions in the rhizosphere and the fraction of distribution at subcellular level in both shoots and roots. It may be concluded that the alleviation of Cr⁶⁺ toxicity by exogenous GSH is directly attributed to its regulation on forms of Cr ions in rhizosphere and their distribution at subcellular levels.     

Proteomic analysis of sensitive and multi drug resistant <Emphasis Type="Italic">Mycobacterium tuberculosis</Emphasis> strains

Multidrug-resistant tuberculosis (MDR-TB) is caused by bacteria that are resistant to the most effective anti TB drugs (Isoniazid and Rifampicin) with or without resistance to other drugs. Novel intervention strategies to eliminate this disease based on finding proteins can be used for designing new drugs or new and reliable kits for diagnosis. The aim of this study was to compare the protein profile of MDR-TB with sensitive isolates. Two-dimensional gel electrophoresis (2DE) along with mass spectrometry is a powerful and effective tool to identification and characterization of Mycobacterium tuberculosis. Two-dimensional gel electrophoresis and matrix assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry was used for diagnosis and comparison of proteins. We identified 14 protein spots in MDR-TB isolates that 2DE analysis showed these spots absent in M. tuberculosis sensitive isolates (Rv1876, Rv0379, Rv0147, Rv2031c, Rv3597c, Rv1886c, MT0493, Rv0440, Rv3614c, Rv1626, Rv0443, Rv0475, Rv3057 and unknown protein. The results showed 22 protein spots which were up regulated (or expressed) by the MDR-TB isolates, (Rv1240, Rv3028c, Rv2971, Rv2114c, Rv3311, Rv3699, Rv1023, Rv1308, Rv3774, Rv0831c, Rv2890c, Rv1392, Rv0719, Rv0054, Rv3418c, Rv0462, Rv2215, Rv2986c, Rv3248c and Rv1908c)). Two up regulated protein spots were identified in sensitive isolate (Rv1133c and Rv0685). These data will provide valuable clues in further investigation for suitable TB rapid tests or drug targets against drug resistant and sensitive of M. tuberculosis.     

Enhancing crop growth, nutrients availability, economics and beneficial rhizosphere microflora through organic and biofertilizers

Field experiment was conducted on fodder maize to explore the potential of integrated use of chemical, organic and biofertilizers for improving maize growth, beneficial microflora in the rhizosphere and the economic returns. The treatments were designed to make comparison of NPK fertilizer with different combinations of half dose of NP with organic and biofertilizers viz. biological potassium fertilizer (BPF), Biopower, effective microorganisms (EM) and green force compost (GFC). Data reflected maximum crop growth in terms of plant height, leaf area and fresh biomass with the treatment of full NPK; and it was followed by BPF+full NP. The highest uptake of NPK nutrients by crop was recorded as: N under half NP+Biopower; P in BPF+full NP; and K from full NPK. The rhizosphere microflora enumeration revealed that Biopower+EM applied along with half dose of GFC soil conditioner (SC) or NP fertilizer gave the highest count of N-fixing bacteria (Azotobacter, Azospirillum, Azoarcus andZoogloea). Regarding the P-solubilizing bacteria,Bacillus was having maximum population with Biopower+BPF+half NP, andPseudomonas under Biopower+EM+half NP treatment. It was concluded that integration of half dose of NP fertilizer with Biopower+BPF / EM can give similar crop yield as with full rate of NP fertilizer; and through reduced use of fertilizers the production cost is minimized and the net return maximized. However, the integration of half dose of NP fertilizer with biofertilizers and compost did not give maize fodder growth and yield comparable to that from full dose of NPK fertilizers.     

Growth of <Emphasis Type="Italic">Helicobacter pylori</Emphasis> in a long spiral form does not alter expression of immunodominant proteins

Background  

We have previously reported that altered culture conditions (a broth media with shaking) could induce a strain of Helicobacter pylori to assume a long spiral morphology resembling that described for Helicobacter heilmannii. The present study was initiated to determine if other strains of H. pylori could be induced to assume that morphology and if doing so would alter the expression of immunodominant proteins.