Advancement in bioprocess technology: parallels between microbial natural products and cell culture biologics

Journal of Industrial Microbiology & Biotechnology - The emergence of natural products and industrial microbiology nearly eight decades ago propelled an era of bioprocess innovation. Half a...     

Phospholipids from the hepatopancreas of Indian horseshoe crab Carcinoscropius rotundicauda

Total phospholipids were extracted from the heart, hepatopancreas, and hemolymph of the Indian horseshoe crab Carcinoscorpius rotundicauda by the conventional method. Characteristic group reaction and 2-dimensional thin-layer chromatography on silica gel were used for identification of different phospholipids. The phospholipid profile obtained from hemolymph and 2 major organs are comparable and show phosphatidyl choline (PC) and phosphatidyl ethanolamine to be the major phospholipids. A phospholipid has been consistently detected migrating immediately below the PC in the thin-layer chromatogram of lipids extracted from the hepatopancreas. When mixed methyl esters of this slower moving PC are resolved on a silica gel plate ran in hexane ether:acetic acid 80:20:1, with appropriate controls, an additional spot is seen just below the normal methyl ester, indicating a difference between the fatty acid compositions of 2 PC (e.g., regular and slower). The slower mixed methyl esters were found to comprise mainly the 4 saturated fatty acids: lauric, myristic, palmitic, and stearic. The slow moving PC seems to consist mainly of molecular species with the above-mentioned saturated fatty acids at both Sn 1 and Sn 2 positions.     

Kinetics of phenol degradation using Pseudomonas putida MTCC 1194

Pseudomonas putida (MTCC 1194) has been used to degrade phenol in water in the concentration range 100–1000?ppm. The inhibition effects of phenol as substrate have become predominant above the concentration of 500?ppm (5.31?mmoles/dm³). The optimum temperature and initial pH required for maximum phenol biodegradation were 30?°C and 7.00 respectively. From the degradation data the activation energy (E _a ) was found to be equal to 13.8?kcal/g mole substrate reacted. The most suitable inoculum age and volume for highest phenol degradation were 12?hrs and 7% v/v respectively. Surfactants had negligible effect on phenol biodegradation process for this microorganism. Monod model has been used to interpret the free cell data on phenol biodegradation. The kinetic parameters have been estimated upto initial concentration of 5.31?mmoles/dm³. μ _max and K _S gradually increased with higher concentration of phenol. However, beyond the phenol concentration of 5.31?mmoles/dm³, the inhibition became prominant. The μ _max has been to be a strong function of initial phenol concentration. The simulated and the experimental phenol degradation profiles have good correspondence with each other.     

Elucidation of trophic interactions in an unusual single-cell nitrogen-fixing symbiosis using metabolic modeling

Marine nitrogen-fixing microorganisms are an important source of fixed nitrogen in oceanic ecosystems. The colonial cyanobacterium Trichodesmium and diatom symbionts were thought to be the primary contributors to oceanic N₂ fixation until the discovery of the unusual uncultivated symbiotic cyanobacterium UCYN-A (Candidatus Atelocyanobacterium thalassa). UCYN-A has atypical metabolic characteristics lacking the oxygen-evolving photosystem II, the tricarboxylic acid cycle, the carbon-fixation enzyme RuBisCo and de novo biosynthetic pathways for a number of amino acids and nucleotides. Therefore, it is obligately symbiotic with its single-celled haptophyte algal host. UCYN-A receives fixed carbon from its host and returns fixed nitrogen, but further insights into this symbiosis are precluded by both UCYN-A and its host being uncultured. In order to investigate how this syntrophy is coordinated, we reconstructed bottom-up genome-scale metabolic models of UCYN-A and its algal partner to explore possible trophic scenarios, focusing on nitrogen fixation and biomass synthesis. Since both partners are uncultivated and only the genome sequence of UCYN-A is available, we used the phylogenetically related Chrysochromulina tobin as a proxy for the host. Through the use of flux balance analysis (FBA), we determined the minimal set of metabolites and biochemical functions that must be shared between the two organisms to ensure viability and growth. We quantitatively investigated the metabolic characteristics that facilitate daytime N₂ fixation in UCYN-A and possible oxygen-scavenging mechanisms needed to create an anaerobic environment to allow nitrogenase to function. This is the first application of an FBA framework to examine the tight metabolic coupling between uncultivated microbes in marine symbiotic communities and provides a roadmap for future efforts focusing on such specialized systems.     

Antitumor activity with nontoxic doses of protein A

Summary This report confirms our previous observation that IV inoculation of purified protein A causes regression of rat mammary adenocarcinomas. In treated tumors, we have obtained histological evidence of changes indicating tumor cell destruction. Protein A treatment does not cause reduction in the body weight or organ weights of rats; nor does it cause any decrease in activity of the enzymes of the microsomal mixed function oxidase system in the liver. Protein A stimulates peripheral white cell counts in normal rats, but not in tumor-bearing rats. We found that protein A infusion reduced (P<0.0005) the level of circulating plasma immune complex concentration. A homing study with ¹²⁵I-labeled protein A indicated that liver, spleen, and kidney tissues are the major sites of protein A accumulation. Therefore, protein A seemed to exert its antitumor effects without causing any generalized toxicity to the system. It is postulated that the action of protein A may be related to its ability to cause a drastic reduction in circulating plasma immune complex concentration, thus potentiating the immune reactivity of the host observed earlier.     

Pentylenetetrazol (PTZ)-kindling development in intact and subcortical structure lesioned rats

Kindling was induced in male wistar rats (280-320 g) by daily ip injections of PTZ in subthreshold doses (30 mg/kg). Repeated administration of PTZ to animals resulted in developing of enhanced seizures and also enhanced seizure susceptibility which could be sustained for a long time (6 months) after last seizure paroxysm. The lesioned hippocampus retarded the manifestation of PTZ kindling, where as lesioned caudate nuclei increased the seizure kindling development. Results also revealed hippocampus as a determinant structure in PTZ kindling formation, which stabilize the epileptic manifestations and make them chronic, at the same time caudate nuclei retarded the epileptic seizures stabilization. This role may be only antiepileptic, and not anti-kindling as is known for caudate nuclei.     

Formulation of Nutrient Medium for In Vitro Somatic Embryo Induction in <Emphasis Type="Italic">Plantago ovata</Emphasis> Forsk

A nutrient medium has been formulated by altering the macro- and micro-elemental concentration in the culture medium for in vitro somatic embryo induction of economically important medicinal plant Plantago ovata Forsk .A comparison was made between induced embryos with normal embryos (produced in Murashige and Skoog (MS) medium) to observe frequency of embryo induction and also to determine regeneration efficiency. In the present investigation, three different media have been formulated. Among them, FM3 (formulated media, treatment 3) was the most suitable for increasing the frequency of somatic embryo production and regeneration of P. ovata Forsk. Better result was obtained using formulated medium than with MS medium.     

Function,regulation and distribution of IsiA,a membrane-bound chlorophyll a-antenna protein in cyanobacteria

Photosynthetica - IsiA is a membrane-bound Chl a-antenna protein synthesized in cyanobacteria under iron deficiency. Since iron deficiency is a common nutrient stress in significant fractions of...