Biofilm inhibition and anti-Candida activity of a cationic lipo-benzamide molecule with twin-nonyl chain

A series of cationic lipo-benzamide compounds with varying lengths of hydrocarbon chains (C2M–C18M) were evaluated for anti-Candida activity. Four compounds harbouring 8–11 hydrocarbon chains demonstrated concentration-dependent inhibition of fungal cell growth with Minimum Inhibitory Concentration (MIC) of ≤6.2?µg?ml^?1. The most active compound (C9M) inhibited growth of both Candida albicans and non-albicans strains and is equally active against pairs of azole sensitive and resistant clinical isolates of C. albicans. Compound C9M also inhibited different stages of Candida biofilms. Scanning Electron Microscopy (SEM) of Candida cells after C9M treatment was also done and no significant cell lysis was observed. Hemolysis assay was performed and only 2.5% haemolysis was observed at MIC concentration.     

Methionine production by microorganisms

Microbial production of methionine is reviewed with 71 references. The review describes different methionine-producing organisms, as well as analog-resistant regulatory mutants, their optimum cultural conditions and yields. The pathways of methionine biosynthesis and their regulation are discussed.     

Isolation of Messenger Ribonucleic Acid for Myosin Heavy Chain

A chicken embryonic polysome fraction that contains 50–60 monoribosomes and synthesizes the heavy chains of myosin is separated from other polysomes of smaller sizes by centrifugation through two cycles of discontinuous and continuous sucrose gradients. The unique properties of the polyadenylic acid segment present at the 3′-end of eukaryotic messenger RNA (mRNA) were used to purify the mRNA for myosin heavy chain from the phenol-extracted total RNA obtained from this polysome fraction. The total RNA was filtered thro ugh millipore filters resulting in partition of the riboscmal RNA (rRNA) and mRNA species. This millipore-bound RNA fraction, which consists of the mRNA and some ribosomal RNAs, was eluted from the filters with sodium dodecyl sulfate (SDS). Subsequent chromatography of this fraction on a cellulose column gave two well-separated peaks: an unadsorbed peak of ribosomal RNAs which was eluted with buffers of high ionic strength and an adsorbed peak of mRNA which was eluted only with a buffer of low ionic strength. Polyacrylamide gel electrophoresis of the mRNA peak fraction showed a single band with no detectable amounts of other RNAs, the mRNA migrating slower than 28S rRNA. The product of in vitro translation of the purified mRNA using a homologous cell-free system was identified as the myosin heavy chain by the following criteria: coprecipitation with carrier myosin at low ionic strength; elution properties on DEAE-cellulose column; and comigration with the heavy chain in polyacrylamide gel electrophoresis. In order to demonstrate the fidelity of translation of the mRNA, ¹⁴C-labeled products of the in vitro translation were copurified with unlabeled myosin heavy chains added as a carrier. The mixture of polypeptides was then cleaved with CNBr and the resulting peptides were separated by molecular sieving. The correlation between the radioactivity and the UV absorbance in the separated peptides indicates that total synthesis of the myosin heavy chain was achieved.     

A Retrospective Study on the Epidemiology of Anthrax,Foot and Mouth Disease,Haemorrhagic Septicaemia,Peste des Petits Ruminants and Rabies in Bangladesh, 2010-2012

Anthrax, foot and mouth disease (FMD), haemorrhagic septicaemia (HS), peste des petits ruminants (PPR) and rabies are considered to be endemic in Bangladesh. This retrospective study was conducted to understand the geographic and seasonal distribution of these major infectious diseases in livestock based on data collected through passive surveillance from 1 January 2010 to 31 December 2012. Data analysis for this period revealed 5,937 cases of anthrax, 300,333 of FMD, 13,436 of HS, 247,783 of PPR and 14,085 cases of dog bite/rabies. While diseases were reported in almost every district of the country, the highest frequency of occurrence corresponded to the susceptible livestock population in the respective districts. There was no significant difference in the disease occurrences between districts bordering India/Myanmar and non-border districts (p>0.05). Significantly higher (p<0.01) numbers of anthrax (84.5%), FMD (88.3%), HS (84.9%) and dog bite/rabies (64.3%) cases were reported in cattle than any other species. PPR cases were reported mostly (94.8%) in goats with only isolated cases (5.2%) in sheep. The diseases occur throughout the year with peak numbers reported during June through September and lowest during December through April, with significant differences (p<0.01) between the months. The annual usages of vaccines for anthrax, FMD, HS and PPR were only 7.31%, 0.61%, 0.84% and 11.59% of the susceptible livestock population, respectively. Prophylactic vaccination against rabies was 21.16% of cases. There were significant differences (p<0.01) in the administration of anthrax, FMD and HS vaccines between border and non-border districts, but not PPR or rabies vaccines. We recommend that surveillance and reporting of these diseases need to be improved throughout the country. Furthermore, all suspected clinical cases should be confirmed by laboratory examination. The findings of this study can be used in the formulation of more effective disease management and control strategies, including appropriate vaccination policies in Bangladesh.     

Functional properties and the oligomeric state of alkyl hydroperoxide reductase subunit F (AhpF) in Pseudomonas aeruginosa

Protoplasma - Alkyl hydroperoxide reductase subunit F (AhpF) is a well-known flavoprotein that transfers electrons from pyridine nucleotides to the peroxidase protein AhpC via redox-active...     

Conserved Ser/Arg-rich motif in PPZ orthologs from fungi is important for its role in cation tolerance

PPZ1 orthologs, novel members of a phosphoprotein phosphatase family of phosphatases, are found only in fungi. They regulate diverse physiological processes in fungi e.g. ion homeostasis, cell size, cell integrity, etc. Although they are an important determinant of salt tolerance in fungi, their physiological role remained unexplored in any halotolerant species. In this context we report here molecular and functional characterization of DhPPZ1 from Debaryomyces hansenii, which is one of the most halotolerant and osmotolerant species of yeast. Our results showed that DhPPZ1 knock-out strain displayed higher tolerance to toxic cations, and unlike in Saccharomyces cerevisiae, Na(+)/H(+) antiporter appeared to have an important role in this process. Besides salt tolerance, DhPPZ1 also had role in cell wall integrity and growth in D. hansenii. We have also identified a short, serine-arginine-rich sequence motif in DhPpz1p that is essential for its role in salt tolerance but not in other physiological processes. Taken together, these results underscore a distinct role of DhPpz1p in D. hansenii and illustrate an example of how organisms utilize the same molecular tool box differently to garner adaptive fitness for their respective ecological niches.