Medium Chain Length Research Articles

Sensing the structural and conformational properties of single-stranded nucleic acids using electrometry and molecular simulations

Inferring the 3D structure and conformation of disordered biomolecules, e.g., single stranded nucleic acids (ssNAs), remains challenging due to their conformational heterogeneity in solution. Here, we use escape-time electrometry (ETe) to measure with sub elementary-charge precision the effective electrical charge in solution of short to medium chain length ssNAs in the range of 5–60 bases. We compare measurements of molecular effective charge with theoretically calculated values for simulated molecular conformations obtained from Molecular Dynamics simulations using a variety of forcefield descriptions. We demonstrate that the measured effective charge captures subtle differences in molecular structure in various nucleic acid homopolymers of identical length, and also that the experimental measurements can find agreement with computed values derived from coarse-grained molecular structure descriptions such as oxDNA, as well next generation ssNA force fields. We further show that comparing the measured effective charge with calculations for a rigid, charged rod—the simplest model of a nucleic acid—yields estimates of molecular structural dimensions such as linear charge spacings that capture molecular structural trends observed using high resolution structural analysis methods such as X-ray scattering. By sensitively probing the effective charge of a molecule, electrometry provides a powerful dimension supporting inferences of molecular structural and conformational properties, as well as the validation of biomolecular structural models. The overall approach holds promise for a high throughput, microscopy-based biomolecular analytical approach offering rapid screening and inference of molecular 3D conformation, and operating at the single molecule level in solution.

Calcium Ion-Coupled Polyphosphates with Different Degrees of Polymerization for Bleeding Control.

The development of efficient hemostatic materials is crucial for achieving rapid hemorrhage control and effective wound healing. Inorganic polyphosphate (polyP) is recognized as an effective modulator of the blood coagulation process. However, the specific effect of polyP chain length on coagulation is not yet fully understood. Furthermore, calcium ions (Ca2+) are essential for the coagulation process, promoting multiple enzyme-catalyzed reactions within the coagulation cascade. Hence, calcium ion-coupled polyphosphate powders with three different degrees of polymerization (CaPP-n, n = 20, 50, and 1500) are synthesized by an ion-exchange reaction. CaPP exhibits a crystalline phase at a low polymerization degree and transitions to an amorphous phase as the polymerization degree increases. Notably, the addition of Ca2+ enhances the wettability of polyP, and CaPP promotes hemostasis, with varying degrees of effectiveness related to chain length. CaPP-50 exhibits the most promising hemostatic performance, with the lowest blood clotting index (BCI, 12.1 ± 0.7%) and the shortest clotting time (302.0 ± 10.5 s). By combining Ca2+ with polyP of medium-chain length, CaPP-50 demonstrates an enhanced ability to accelerate the adhesion and activation of blood cells, initiate the intrinsic coagulation cascade, and form a stable blood clot, outperforming both CaPP-20 and CaPP-1500. The hemostatic efficacy of CaPP-50 is further validated using rat liver bleeding and femoral artery puncture models. CaPP-50 is proven to possess hemostatic properties comparable to those of commercial calcium-based zeolite hemostatic powder and superior to kaolin. In addition, CaPP-50 exhibits excellent biocompatibility and long-term storage stability. These results suggest that CaPP-50 has significant clinical and commercial potential as an active inorganic hemostatic agent for rapid control of bleeding.

Tailoring the structural and physicochemical properties of rice straw cellulose-based cryogels by cell-mediated polyhydroxyalkanoate deposition

This study presents a novel biotechnological approach for creating water vapor-resistant cryogels with improved integrity. Rice straw cellulose was transformed into nanofibrils through TEMPO-mediated oxidation and high-pressure homogenization. The resulting cryogels remained firm even when immersed in aqueous media, whose pores were used by live cell to deposit polyhydroxyalkanoate (PHA) particles inside them. This novel method allowed the compatibilization of PHA within the cellulosic fibers. As a consequence, the water sorption capacity was decreased by up to 6 times having just 4 % of PHA compared to untreated cryogels, preserving the cryogel density and elasticity. Additionally, this technique can be adapted to various bacterial strains and PHA types, allowing for further optimization. It was demonstrated that the amount and type of PHA (medium chain length and small chain length-PHA) used affects the properties for the cryogels, especially the water vapor sorption behavior and the compressive strength. Compared to traditional coating methods, this cell-mediated approach not only allows to distribute PHA on the surface of the cryogel, but also ensures polymer penetration throughout the cryogel due to bacterial self-movement. This study opens doors for creating cryogels with tunable water vapor sorption and other additional functionalities through the use of specialized PHA variants.

Diversity analysis of cyanobacterial flora from the Tatapani Hot Spring of Chhattisgarh and exploration of their industrially as well as environmentally valuable properties

The present study investigates the cyanobacterial diversity of Tatapani hot spring, Chhattisgarh, India, using a polyphasic approach, their pigment system, biofuel properties and ability to bioremediate emerging pollutant triclosan. While the microscopic analyses of the natural samples reflected high cyanobacterial diversity with all morpho-forms, physicochemical studies revealed temperature being the major factor affecting the cyanobacterial distribution in the hot spring. Among the 22 collected cyanobacterial samples, 14 were grown successfully under laboratory conditions and 10 of them showed optimum growth at 45 °C. However, four strains displayed preference for lower temperature (27 °C) for optimum growth. The polyphasic characterization of 14 strains revealed that all the thermophiles belonged to the genus Mastigocladus whereas the strains Sytonema sp. TPJ-3, Calothrix sp. TPB-2, Westiellopsis sp. TPR-29 and Desikacharya sp. TPB-4 constituted the group of mesophiles. Calothrix sp. TPB-2 was identified as a novel genus (Neocalothrix thermalis) based on distinct morphology and phylogenetic position with unique ITS folding pattern. Additionally, our study disclosed the production of comparatively higher amounts of pigments and medium chain length fatty acids (C16 to C18) by the thermophilic strains, which indicated their potential to be used as feedstocks for pigments and biofuel production respectively. Although the triclosan bioremediation study reflected considerable triclosan removal efficiencies of all the strains, most impressive results were observed in case of Westiellopsis sp. TPR-29 (93.08 %) and Mastigocladus sp. TA-8 (91.92 %). Moreover, the in-silico study-based revelation of high triclosan binding ability of cyanobacterial laccase (−5.8 and − 5.4 kcal/mol) and catechol 2,3-dioxygenase (−5.9 and − 6.0 kcal/mol) suggested the probable triclosan degrading potential of Westiellopsis and Mastigocladus. Conclusively, the Tatapani hot spring represents a unique environment with the dominance of true-branched heterocytous thermophilic cyanobacteria that have enormous potential to remove triclosan and produce high amounts of pigments and medium chain length fatty acids.

Recent advances in liquid-phase NMR of the coal-derived products.

Present review focuses on the most recent advances in a liquid-phase nuclear magnetic resonance (NMR) of the coal-derived products-coal tar pitches, asphaltenes, and humic and fulvic acids, covering exclusively the results in the liquid-phase NMR studies leaving apart an overwhelming amount of publications dealing with the solid-state NMR investigations in this field (which are comprehensively reviewed elsewhere). Owing to the complexity of the coal-derived products, their 1H and 13C NMR spectra consist of a number of overlapping signals belonging to different hydrocarbon types. Comprehensive studies of coal tar pitches, asphaltenes, and humic and fulvic acids by means of NMR over the past several decades revealed characteristic functional groups of those fractions together with spectral regions in which they resonate. Quantitative 1H and 13C NMR spectra characterize aromatic and saturated carbons spread over many structural moieties, which provides a solid guideline into molecular structure of the coal-derived products. Nowadays, quantitative 13C NMR measurements yield information about a variety of structural parameters such as functional group distribution, aromaticity, degree of condensation of aromatic rings, and medium chain lengths together with many other more specific parameters. The structural NMR studies of coal and coal-derived products are developing on a backdrop of a marked progress in computational NMR. At present, we are witnessing an unprecedentedly fast development of theoretical and computational methods in the field of NMR spectroscopy. Discussed in the present review are the most recent advances in the NMR studies of the processing products of peat, lignite or brown coal, anthracite or hard coal, and graphite in solution, like coal tar pitches, asphaltenes, and humic and fulvic acids.

3D Melt-Extrusion Printing of Medium Chain Length Polyhydroxyalkanoates and Their Application as Antibiotic-Free Antibacterial Scaffolds for Bone Regeneration.

In this work, we investigated, for the first time, the possibility of developing scaffolds for bone tissue engineering through three-dimensional (3D) melt-extrusion printing of medium chain length polyhydroxyalkanoate (mcl-PHA) (i.e., poly(3-hydroxyoctanoate-co-hydroxydecanoate-co-hydroxydodecanoate), P(3HO-co-3HD-co-3HDD)). The process parameters were successfully optimized to produce well-defined and reproducible 3D P(3HO-co-3HD-co-3HDD) scaffolds, showing high cell viability (100%) toward both undifferentiated and differentiated MC3T3-E1 cells. To introduce antibacterial features in the developed scaffolds, two strategies were investigated. For the first strategy, P(3HO-co-3HD-co-3HDD) was combined with PHAs containing thioester groups in their side chains (i.e., PHACOS), inherently antibacterial PHAs. The 3D blend scaffolds were able to induce a 70% reduction of Staphylococcus aureus 6538P cells by direct contact testing, confirming their antibacterial properties. Additionally, the scaffolds were able to support the growth of MC3T3-E1 cells, showing the potential for bone regeneration. For the second strategy, composite materials were produced by the combination of P(3HO-co-3HD-co-HDD) with a novel antibacterial hydroxyapatite doped with selenium and strontium ions (Se-Sr-HA). The composite material with 10 wt % Se-Sr-HA as a filler showed high antibacterial activity against both Gram-positive (S. aureus 6538P) and Gram-negative bacteria (Escherichia coli 8739), through a dual mechanism: by direct contact (inducing 80% reduction of both bacterial strains) and through the release of active ions (leading to a 54% bacterial cell count reduction for S. aureus 6538P and 30% for E. coli 8739 after 24 h). Moreover, the composite scaffolds showed high viability of MC3T3-E1 cells through both indirect and direct testing, showing promising results for their application in bone tissue engineering.

Fatty acid-derived ionic liquids as soft and sustainable antimicrobial agents

In this study, two sustainability goals are addressed: 1) developing new soft antimicrobial agents (to control antimicrobial resistance) and 2) using natural bio-derived components for this purpose. Fatty acids of bio-renewable origin (stearin, palm kernel and coconut oils) were found to be excellent starting materials for obtaining ester-functionalized ionic liquids (ILs) and mixtures. A series of soft antimicrobial agents based on imidazolium, pyridinium and cholinium ILs with long alkyl ester chains were synthesized, and their properties were examined. The length of the alkyl chain had a notable effect on the physicochemical and biological properties of the synthesized materials. The introduction of a butyl linker and an ester bond lowered the melting point, increased the antimicrobial effectiveness and reduced the cytotoxicity compared to those of non-functionalized ILs with the same hydrocarbon chain. ILs and mixtures with medium chain lengths (C12, C13 and C15) were recognized as promising substitutes for demanding cationic antimicrobial agents. The presence of an ester bond connecting the polar head and hydrophobic tail can promote the breakdown of amphiphilic molecules into less toxic initial compounds. These findings make an important contribution to the development of new, effective amphiphiles with broad-spectrum antimicrobial activity and lower environmental impact.

Defluorination of monofluorinated alkane by Rhodococcus sp. NJF-7 isolated from soil

Microbial degradation of fluorinated compounds raised significant attention because of their widespread distribution and potential environmental impacts. Here, we report a bacterial isolate, Rhodococcus sp. NJF-7 capable of defluorinating monofluorinated medium-chain length alkanes. This isolate consumed 2.29 ± 0.13 mmol L− 1 of 1-fluorodecane (FD) during a 52 h incubation period, resulting in a significant release of inorganic fluoride amounting to 2.16 ± 0.03 mmol L− 1. The defluorination process was strongly affected by the initial FD concentration and pH conditions, with lower pH increasing fluoride toxicity to bacterial cells and inhibiting enzymatic defluorination activity. Stoichiometric conversion of FD to fluoride was observed at neutral pH with resting cells, while defluorination was significantly lower at reduced pH (6.5). The discovery of the metabolites decanoic acid and methyl decanoate suggests that the initial attack by monooxygenases may be responsible for the biological defluorination of FD. The findings here provide new insights into microbial defluorination processes, specifically aiding in understanding the environmental fate of organic semi-fluorinated alkane chemicals.

Medium Chain Length Polyhydroxyalkanoate Production by Engineered Pseudomonas gessardii Using Acetate-formate as Carbon Sources.

Production of medium chain length polyhydroxyalkanoate (mcl-PHA) was attempted using Pseudomonas gessardii NIBRBAC000509957, which was isolated from Sunchang, Jeollabuk-do, Republic of Korea (35°24'27.7"N, 127°09'13.0"E) and effectively utilized acetate and formate as carbon sources. We first evaluated the utilization of acetate as a carbon source, revealing optimal growth at 5g/L acetate. Then, formate was supplied to the acetate minimal medium as a carbon source to enhance cell growth. After overexpressing the acetate and formate assimilation pathway enzymes, this strain grew at a significantly higher rate in the medium. As this strain naturally produces PHA, it was further engineered metabolically to enhance mcl-PHA production. The engineered strain produced 0.40g/L of mcl-PHA with a biomass content of 30.43% in fed-batch fermentation. Overall, this strain can be further developed to convert acetate and formate into valuable products.

Integrating chemical and biological technologies in upcycling plastic waste to medium-chain α,ω-Diacid

The growing accumulation of plastic waste poses a pressing environmental challenge. Traditional disposal methods, such as incineration and landfilling, carry considerable health and ecological risks. In response, our study presents an innovative method to repurpose mixed plastic waste into valuable α,ω-diacids utilizing chemo-biological processes. We extracted pyrolysis oil, rich in hydrocarbons spanning a broad range of chain lengths (C7 to C32), from household plastic waste and employed a genetically engineered β-oxidation-blocked Candida tropicalis strain to convert this oil into α,ω-diacids of various chain lengths. Simple distillation at 200 °C enabled the extraction of medium-chain hydrocarbons from the pyrolysis oil. However, an increased ratio of medium-chain alkenes posed a toxicity challenge to the cells. Through hydrogenation, these medium-chain alkenes were fully converted to alkanes. Remarkably, cell growth was maintained even with an 8% concentration of hydrogenates. The subsequent biotransformation yielded medium-chain diacids, with 94.3% of the produced α,ω-diacids being of medium-chain length (C7 to C14). These results offer a novel and scalable solution for converting everyday plastic waste into valuable chemicals, thus significantly contributing to the circular economy and the advancement of sustainability goals.

Production of Medium Chain Length Polyhydroxyalkanoate from Waste Cannabis sativa Biomass

This works aims to evaluate a process to convert residual medical Cannabis sativa stalks into medium chain length polyhydroxyalkanoate (mcl-PHA), using chemical pretreatment and enzymatic hydrolysis to obtain sugars as a carbon source for a fermentation process with Pseudomonas aeruginosa. Chemical composition analysis revealed a content of structural polysaccharides of 57.64%. Thermochemical pretreatments with 2% sulfuric acid or 2% sodium hydroxide were capable of partially removing hemicellulose and lignin, as well as increasing cellulose crystallinity. Pretreated biomass was subjected to hydrolysis using commercial cellulase cocktails Celluclast® 1.5 L and Cellic® CTec3. Acid pretreatment showed an adverse effect on hydrolysis yield of holocellulose, decreasing to 39.5%; compared to 44.4% of untreated biomass. Alkaline pretreatment increased degree of hydrolysis up to 73.3%. Shake flask fermentation of hydrolysate with Pseudomonas aeruginosa produced cell growth of 1.65 g/L and a mcl-PHA titer of 0.41 g/L. Extracted polymer presented characteristic FTIR bands for PHAs, glass transition temperature of − 50.8 °C, melting temperature of 48.9 °C, possibly allowing its use in the biomedical industry. The developed process represents a potential way to valorize Cannabis waste stalks, using alkaline pretreatment, enzymatic hydrolysis with Celluclast® 1.5 L and fermentation with Pseudomonas aeruginosa. Further work should focus on improving yield of the obtained polyhydroxyalkanoate in fermentation, in order to improve industrial feasibility of the entire process and, in turn, increasing revenue of the medical Cannabis industry.Graphical

Pseudomonas putida as a platform for medium-chain length α,ω-diol production: Opportunities and challenges.

Medium-chain-length α,ω-diols (mcl-diols) play an important role in polymer production, traditionally depending on energy-intensive chemical processes. Microbial cell factories offer an alternative, but conventional strains like Escherichia coli and Saccharomyces cerevisiae face challenges in mcl-diol production due to the toxicity of intermediates such as alcohols and acids. Metabolic engineering and synthetic biology enable the engineering of non-model strains for such purposes with P. putida emerging as a promising microbial platform. This study reviews the advancement in diol production using P. putida and proposes a four-module approach for the sustainable production of diols. Despite progress, challenges persist, and this study discusses current obstacles and future opportunities for leveraging P. putida as a microbial cell factory for mcl-diol production. Furthermore, this study highlights the potential of using P. putida as an efficient chassis for diol synthesis.

Friction of a driven chain: role of momentum conservation, Goldstone and radiation modes

We analytically study friction and dissipation of a driven bead in a 1D harmonic chain, and analyze the role of internal damping mechanism as well as chain length. Specifically, we investigate Dissipative Particle Dynamics and Langevin Dynamics, as paradigmatic examples that do and do not display translational symmetry, with distinct results: For identical parameters, the friction forces can differ by many orders of magnitude. For slow driving, a Goldstone mode traverses the entire system, resulting in friction of the driven bead that grows arbitrarily large (Langevin) or gets arbitrarily small (Dissipative Particle Dynamics) with system size. For a long chain, the friction for DPD is shown to be bound, while it shows a singularity (i.e. can be arbitrarily large) for Langevin damping. For long underdamped chains, a radiation mode is recovered in either case, with friction independent of damping mechanism. For medium length chains, the chain shows the expected resonant behavior. At the resonance, friction is non-analytic in damping parameter γ, depending on it as γ −1. Generally, no zero frequency bulk friction coefficient can be determined, as the limits of small frequency and infinite chain length do not commute, and we discuss the regimes where ‘simple’ macroscopic friction occurs.

Investigating the anti-bioadhesion properties of short, medium chain length, and amphiphilic polyhydroxyalkanoate films

Silicone materials are widely used in fouling release coatings, but developing eco-friendly protection via biosourced coatings, such as polyhydroxyalcanoates (PHA) presents a major challenge. Anti-bioadhesion properties of medium chain length PHA and short chain length PHA films are studied and compared with a reference Polydimethylsiloxane coating. The results highlight the best capability of the soft and low-roughness PHA-mcl films to resist bacteria or diatoms adsorption as compared to neat PDMS and PHBHV coatings. These parameters are insufficient to explain all the results and other properties related to PHA crystallinity are discussed. Moreover, the addition of a low amount of PEG copolymers within the coatings, to create amphiphilic coatings, boosts their anti-adhesive properties. This work reveals the importance of the physical or chemical ambiguity of surfaces in their anti-adhesive effectiveness and highlights the potential of PHA-mcl film to resist the primary adhesion of microorganisms.

Diversity in fatty acid elongation enzymes: The FabB long-chain β-ketoacyl-ACP synthase I initiates fatty acid synthesis in Pseudomonas putida F1

The condensation of acetyl-CoA with malonyl-acyl carrier protein (ACP) by β-ketoacyl-ACP synthase III (KAS III, FabH) and decarboxylation of malonyl-ACP by malonyl-ACP decarboxylase are the two pathways that initiate bacterial fatty acid synthesis (FAS) in Escherichia coli. In addition to these two routes, we report that Pseudomonas putida F1 β-ketoacyl-ACP synthase I (FabB), in addition to playing a key role in fatty acid elongation, also initiates FAS invivo. We report that although two P.putida F1 fabH genes (PpfabH1 and PpfabH2) both encode functional KAS III enzymes, neither is essential for growth. PpFabH1 is a canonical KAS III similar to E.coli FabH whereas PpFabH2 catalyzes condensation of malonyl-ACP with short- and medium-chain length acyl-CoAs. Since these two KAS III enzymes are not essential for FAS in P.putida F1, we sought the P.putida initiation enzyme and unexpectedly found that it was FabB, the elongation enzyme of the oxygen-independent unsaturated fatty acid pathway. P.putida FabB decarboxylates malonyl-ACP and condenses the acetyl-ACP product with malonyl-ACP for initiation of FAS. These data show that P.putida FabB, unlike the paradigm E.coli FabB, can catalyze the initiation reaction in FAS.

Degradation kinetics of medium chain length Polyhydroxyalkanoate degrading enzyme: a quartz crystal microbalance study.

This study investigates the enzymatic degradation processes of different classes of polyhydroxyalkanoates (PHAs), a group of biopolymers naturally synthesized by various microorganisms. Medium chain length PHAs (mcl-PHAs) are distinguished biopolymers due to their biodegradability and diverse material properties. Using quartz crystal microbalance measurements as a valuable tool for accurate real-time monitoring of the enzymatic degradation process, the research provides detailed kinetic data, describing the interaction between enzymes and substrates during the enzymatic degradation process. Thin films of poly-3-hydroxybutyrate (PHB) and polyhydroxyoctanoate copolymer (PHO), containing molar fractions of about 84% 3-hydroxyoctanoate and 16% 3-hydroxyhexanoate, were exposed to scl-depolymerases from Pseudomonas lemoignei LMG 2207 and recombinant mcl-depolymerase produced in Escherichia coli DH5α harboring the plasmid pMAD8, respectively. Analyses based on a heterogeneous kinetic model for the polymer degradation indicated a six-fold stronger adsorption equilibrium constant of mcl-depolymerase to PHO. Conversely, the degradation rate constant was approximately twice as high for scl-depolymerases acting on PHB. Finally, the study highlights the differences in enzyme-substrate interactions and degradation mechanisms between the investigated scl- and mcl-PHAs.

Influence of quicklime and Portland cement, as alkaline activators, on the reaction products of supersulfated cements based on pumice

This is a study of the microstructure and chemical, mineralogical and structural composition of the reaction products of supersulfated cements based on pumice (SSC-PM), prepared with 20 % of quicklime or Portland cement, as alkaline activators, and 5–10 % of a sulfatic activator of anhydrite (An). Paste specimens were cured at 20 °C or 60 °C for 24 h. The characterization by FTIR, DRX, DTA/TGA, SEM, EDS and NMR indicated the type of alkaline activator influenced the type and amount of hydration products, as well as the resulting microstructure, which in turn affects the compressive strength. After 28 days, the quicklime favored the pumice dissolution, leading to degrees of reaction higher than with Portland cement, promoting the conversion AlIV→ AlVI in the reaction products to form high amounts of ettringite (AFt ≥27 %) and reducing aluminum uptake into the C–S–H on Q2 and Q3 sites with an AlIV/Si ≤ 0.06. On the other hand, the Portland cement increased the medium chain length (MCL) and favored the intertwining of long needle-shaped AFt with the C-A-S-H, densifying the microstructure, favoring the compressive strength. The best strength of 24 MPa was for a binder with 5%An-20%PC (ICT:60 °C) with MCL = 9 (Ca/Si = 0.94).

Fabrication and biological properties of artificial tendon composite from medium chain length polyhydroxyalkanoate

Medium chain length polyhydroxyalkanoate (MCL-PHA), a biodegradable and biocompatible material, has a mechanical characteristic of hyper-elasticity, comparable to elastomeric material with similar properties to human tendon flexibility. These MCL-PHA properties gave rise to applying this material as an artificial tendon or ligament implant. In this study, the material was solution-casted in cylinder and rectangular shapes in the molds with the designated small holes. A portion of the torn human tendon was threaded into the holes as a suture to generate a composite tendon graft. The tensile testing of the three types of MCL-PHA/tendon composite shows that the cylinder material shape with the zigzag threaded three holes has the highest value of maximum tensile strength at 56 MPa, closing to the ultimate tendon tensile stress (50–100 MPa). Fibroblast cells collected from patients were employed as primary tendon cells for growing to attach to the surface of the MCL-PHA material to prove the concept of the composite tendon graft. The cells could attach and proliferate with substantial viability and generate collagen, leading to chondrogenic induction of tendon cells. An in vivo biocompatibility was also conducted in a rat subcutaneous model in comparison with medical-grade silicone. The MCL-PHA material was found to be biocompatible with the surrounding tissues. For surgical application, after the MCL-PHA material is decomposed, tendon cells should develop into an attached tendon and co-generated as a tendon graft.

Bioconversion of glycerol into polyhydroxyalkanoates through an atypical metabolism shift using Priestia megaterium during fermentation processes: A statistical analysis of carbon and nitrogen source concentrations

Polyhydroxyalkanoates (PHA) are bioplastics which are well known as intracellular energy storage compounds and are produced in a large number of prokaryotic species. These bio-based inclusions are biodegradable, biocompatible and environmental friendly. Industrial production of, short chain and medium chain length PHA, involves the use of microorganisms and their enzymes. Priestia megaterium previously known as Bacillus megaterium is a well-recognized bacterium for producing short chain length PHA. This study focuses to characterize this bacterium for the production of medium chain length PHA, and a novel blend of both types of monomers having enhanced properties and versatile applications. Statistical analyses and simulations were used to demonstrate that cell dry weight can be derived as a function of OD600 and PHA content. Optimization of growth conditions resulted in the maximum PHA production as: 0. 05 g. g-x. H−1, where the rate of PHA production was 0.28 g L−1. H−1 and PHA concentration was 4.94 g. L−1. This study also demonstrated FTIR to be a semi quantitative tool for PHA production. Moreover, conversion of scl-PHA to mcl-PHA with reference to time intermissions using GC-FID are shown.

Patterns of Variation in the Usage of Fatty Acid Chains among Classes of Ester and Ether Neutral Lipids and Phospholipids in the Queensland Fruit Fly.

Modern lipidomics has the power and sensitivity to elucidate the role of insects' lipidomes in their adaptations to the environment at a mechanistic molecular level. However, few lipidomic studies have yet been conducted on insects beyond model species such as Drosophila melanogaster. Here, we present the lipidome of adult males of another higher dipteran frugivore, Bactrocera tryoni. We describe 421 lipids across 15 classes of ester neutral lipids and phospholipids and ether neutral lipids and phospholipids. Most of the lipids are specified in terms of the carbon and double bond contents of each constituent hydrocarbon chain, and more ether lipids are specified to this degree than in any previous insect lipidomic analyses. Class-specific profiles of chain length and (un)saturation are broadly similar to those reported in D. melanogaster, although we found fewer medium-length chains in ether lipids. The high level of chain specification in our dataset also revealed widespread non-random combinations of different chain types in several ester lipid classes, including deficits of combinations involving chains of the same carbon and double bond contents among four phospholipid classes and excesses of combinations of dissimilar chains in several classes. Large differences were also found in the length and double bond profiles of the acyl vs. alkyl or alkenyl chains of the ether lipids. Work on other organisms suggests some of the differences observed will be functionally consequential and mediated, at least in part, by differences in substrate specificity among enzymes in lipid synthesis and remodelling pathways. Interrogation of the B. tryoni genome showed it has comparable levels of diversity overall in these enzymes but with some gene gain/loss differences and considerable sequence divergence from D. melanogaster.