Organophosphate pesticides an emerging environmental contaminant: Pollution, toxicity, bioremediation progress, and remaining challenges.

Organophosphates (OPs) are an integral part of modern agriculture; however, due to overexploitation, OPs pesticides residues are leaching and accumulating in the soil, and groundwater contaminated terrestrial and aquatic food webs. Acute exposure to OPs could produce toxicity in insects, plants, animals, and humans. OPs are known for covalent inhibition of acetylcholinesterase enzyme in pests and terrestrial/aquatic organisms, leading to nervous, respiratory, reproductive, and hepatic abnormalities. OPs pesticides also disrupt the growth-promoting machinery in plants by inhibiting key enzymes, permeability, and trans-cuticular diffusion, which is crucial for plant growth. Excessive use of OPs, directly/indirectly affecting human/environmental health, raise a thoughtful global concern. Developing a safe, reliable, economical, and eco-friendly methods for removing OPs pesticides from the environment is thus necessary. Bioremediation techniques coupled with microbes or microbial-biocatalysts are emerging as promising antidotes for OPs pesticides. Here, we comprehensively review the current scenario of OPs pollution, their toxicity (at a molecular level), and the recent advancements in biotechnology (modified biocatalytic systems) for detection, decontamination, and bioremediation of OP-pesticides in polluted environments. Furthermore, the review focuses on onsite applications of OPs degrading enzymes (immobilizations/biosensors/others), and it also highlights remaining challenges with future approaches.

Bio-catalytic system of metallohydrolases for remediation of neurotoxin organophosphates and applications with a future vision.

Organophosphates (OPs) compounds are universally used as pesticides and maintained as chemical warfare agents by many nations across the globe. These OPs compounds due to their molecular structure are highly persistent in nature, contaminating soil and water equally, thereby adversely affecting terrestrial and aquatic life, and contributing to millions of poisoning cases every year worldwide. Therefore, there are urgent requirements for safe and rapid method for environmental restoration and therapeutic detoxications. Organophosphate hydrolyzing enzymes are emerging as an attractive candidate for the degradation of OPs compounds. The biologically driven approach is safe, rapid, and environment-friendly. As genetically modified microbes are not in practice worldwide, scientists are exploring different bioremediation approaches that mainly focus on cell-free biocatalytic systems. In this review, we have discussed the prevalence of OPs hydrolyzing enzymatic systems and the recent advancement of enzyme engineering in enhancing the catalytic activity, substrate specificity, and half-life. It highlights the application in OPs detection, decontamination (environmental bioremediation), and therapeutic detoxification using approaches like immobilization. We have also described the remaining challenges and future prospects.

Improved live-cell PCR method for detection of organophosphates degrading opd genes and applications.

Organophosphates are becoming an emerging pollutant due to their various applications, particularly as pesticides. In this study, an improved Colony (Live-cell) PCR method was developed for the detection of opd genes from bacteria encoding the organophosphate hydrolase enzymes capable of degrading various organophosphates. The improved method does not require pre-heating or pre-lysis of bacterial cells as essential in the conventional colony PCR. The reaction volume was scaled down to 10 µl by optimizing the PCR buffer and amplification conditions. The improved method was used for Gram positive and negative bacteria, glycerol stocks, liquid cultures, recombinant and mutant strains. Also, 16S rRNA gene was amplified from unknown environmental isolates and known E. coli strains. The amplified opd and 16S rRNA genes from the improved colony PCR method and by conventional PCR were sequenced, and similar results were obtained from both techniques. Thus, the improved method can be further explored in molecular biology or during biomarker studies. KEY POINTS: • Improved colony PCR method was developed for screening of opd genes from bacteria. • Method was validated for Gram positive/negative bacteria from solid as well as liquid media. • The improved method was rapid, efficient, and can be applied under various conditions.

A novel organophosphate hydrolase from Arthrobacter sp. HM01: Characterization and applications.

Bioremediation systems coupled to efficient microbial enzymes have emerged as an attractive approach for the in-situ removal of hazardous organophosphates (OPs) pesticides from the polluted environment. However, the role of engineered enzymes in OPs-degradation is rarely studied. In this study, the potential OPs-hydrolase (opdH) gene (Arthrobacter sp. HM01) was isolated, cloned, expressed, and purified. The recombinant organophosphate hydrolase (ropdH) was âˆ¼29 kDa; which catalyzed a broad-range of OPs-pesticides in organic-solvent (∼99 % in 30 min), and was found to increase the catalytic efficiency by 10-folds over the native enzyme (kcat/Km: 107 M-1s-1). The degraded metabolites were analyzed using HPLC/GCMS. Through site-directed mutagenesis, it was confirmed that, conserved metal-bridged residue (Lys-127), plays a crucial role in OPs-degradation, which shows âˆ¼18-folds decline in OPs-degradation. Furthermore, the catalytic activity and its stability has been enhanced by >2.0-fold through biochemical optimization. Thus, the study suggests that ropdH has all the required properties for OPs bioremediation.

Degradation insight of organophosphate pesticide chlorpyrifos through novel intermediate 2,6-dihydroxypyridine by Arthrobacter sp. HM01.

Organophosphates (OPs) are hazardous pesticides, but an indispensable part of modern agriculture; collaterally contaminating agricultural soil and surrounding water. They have raised serious food safety and environmental toxicity that adversely affect the terrestrial and aquatic ecosystems and therefore, it become essential to develop a rapid bioremediation technique for restoring the pristine environment. A newly OPs degrading Arthrobacter sp. HM01 was isolated from pesticide-contaminated soil and identified by a ribotyping (16S rRNA) method. Genus Arthrobacter has not been previously reported in chlorpyrifos (CP) degradation, which shows 99% CP (100 mg L-1) degradation within 10 h in mMSM medium and also shows tolerance to a high concentration (1000 mg L-1) of CP. HM01 utilized a broad range of OPs pesticides and other aromatic pollutants including intermediates of CP degradation as sole carbon sources. The maximum CP degradation was obtained at pH 7 and 32 °C. During the degradation, a newly identified intermediate 2,6-dihydroxypyridine was detected through TLC/HPLC/LCMS analysis and a putative pathway was proposed for its degradation. The study also revealed that the organophosphate hydrolase (opdH) gene was responsible for CP degradation, and the opdH-enzyme was located intracellularly. The opdH enzyme was characterized from cell free extract for its optimum pH and temperature requirement, which was 7.0 and 50 °C, respectively. Thus, the results revealed the true potential of HM01 for OPs-bioremediation. Moreover, the strain HM01 showed the fastest rate of CP degradation, among the reported Arthrobacter sp.

Draft Genome Analysis of Acinetobacter indicus Strain UBT1, an Efficient Lipase and Biosurfactant Producer.

Acinetobacter indicus strain UBT1 has shown efficient lipase (243 U ml-1) and biosurfactant (61.1% E24% emulsification and surface tension reduction to 37.7 mN m-1) production capabilities using agro-industrial waste as sole carbon source. We report here the draft genome sequence of A. indicus strain UBT1 having genome size of 2.97 Mb with 45.90% GC content. Total 2721 coding genes were predicted using National Center for Biotechnology Information-Prokaryotic Genome Annotation Pipeline (NCBI-PGAP). The whole genome shotgun project sequence data are accessible through NCBI Gene Bank under accession no. JABFOI000000000. PGAP annotation revealed the presence of the triacylglycerol lipase, phospholipase etc., that circuitously confers the oil consumption competency to the strain UBT1. Rapid Annotation using the Subsystem Technology (RAST) server used for mapping the genes to the subsystem resulted in 278 subsystem with 30% subsystem coverage. The draft genome data can be used to exploit the A. indicus strain UBT1 for its advance biotechnological application and also for further comparative genomic studies.

Optimization of organic solvent-tolerant lipase production by Acinetobacter sp. UBT1 using deoiled castor seed cake.

Organic solvent-tolerant lipase-producing microorganisms were isolated from petrol spilled soil. From ten morphologically distinct lipase-producing bacterial isolates, highest amount of lipase-producing isolate UBT1 was identified as Acinetobacter sp. using 16S rRNA gene sequencing (NCBI Accession No: MH879815). An increase in lipase production from 42 U/mL to 243 U/mL was obtained when different deoiled seed cakes were supplemented instead of olive oil in the medium. Further optimization of media components by the statistical approach assisted in discerning the main influencing media components and their optimum concentrations. Nine components glucose, castor seedcake, potassium nitrate, gum arabic, calcium chloride, magnesium sulphate, potassium di-hydrogen phosphate, dipotassium hydrogen phosphate, and ferric chloride were selected for Plackett-Burman design. The optimum concentrations of three significant selected components for the lipase production were found to be 0.025 gm% glucose, 0.002 gm% calcium chloride, and 0.2 gm% potassium di-hydrogen phosphate as determined by Response Surface Methodology. Increase in lipase production with 292.29 U/mL was achieved in the media containing optimized components and 2 gm% deoiled castor seed cake. Purification studies with ammonium sulphate precipitation, dialysis, and gel permeation chromatography resulted in 77.54% recovery with 5.77-fold partially purified lipase. The residual activity of lipase in 50 and 75% concentration of n-hexane among other solvents after 24 h was 105.05 and 90.42%, respectively, indicating its solvent tolerance. The present study reports the isolation of organic solvent-tolerant lipase-producing Acinetobacter sp. UBT1, optimization of the culture media for lipase production using the deoiled castor seed cake, and its partial purification.

Cyanobacterial diversity in mat sample obtained from hypersaline desert, Rann of Kachchh.

Rann of Kachchh (RoK) is a unique geoformation, which is exposed to dynamic environmental changes such as salinity, temperature, and nutrients throughout the year. In this study, the pooled mat sample was examined for the cyanobacterial community structure using culture-dependent and culture-independent approaches. Taxonomic profiling was studied using amplicon sequencing that revealed the enrichment of Pseudanabaenales and Oscillatoriales by QIIME and MG-RAST, respectively. Other abundant orders were represented by Chroococcales, Nostocales, and unclassified cyanobacteria by both approaches. Nine cyanobacterial cultures were isolated from mat samples showing 90-98% similarities with available sequences in GenBank. The culture-dependent study suggested that mat was dominated by cyanobacterial orders such as Oscillatoriales-filamentous and Chroococcales-unicellular. Our results from the culture-dependent approach also indicated that despite high similarities in gene sequences, six cyanobacteria fall into the separate clade in the phylogenetic analysis that could be signs of evolution due to an extreme environment. Cultured isolates are correlated well with abundant taxa from amplicon sequencing. Further, protein profiling was done specifically for phycobiliproteins which will be helpful to elucidate their roles in light harvesting and energy transfer mechanism in the unique environment of RoK.

Draft genome sequence of a thermostable, alkaliphilic α-amylase and protease producing Bacillus amyloliquefaciens strain KCP2.

Bacillus amyloliquefaciens strain KCP2 was isolated from municipal food waste samples collected in Vallabh Vidyanagar, Gujarat, India. Strain KCP2 is noteworthy due to its ability to produce a thermostable, alkaliphilic α-amylase and a protease. These enzymes have importance in several industrial processes including bread making, brewing, starch processing, pharmacy, and textile industries. Whole genome sequencing of strain KCP2 showed that the estimated genome size was 3.9 Mb, the G + C content was 46%, and it coded for 4113 genes.

ß-Cyclodextrin Production by Cyclodextrin Glucanotransferase from an Alkaliphile Microbacterium terrae KNR 9 Using Different Starch Substrates.

Cyclodextrin glucanotransferase (CGTase, EC 2.4.1.19) is an important member of α-amylase family which can degrade the starch and produce cyclodextrins (CDs) as a result of intramolecular transglycosylation (cyclization). ß-Cyclodextrin production was carried out using the purified CGTase enzyme from an alkaliphile Microbacterium terrae KNR 9 with different starches in raw as well as gelatinized form. Cyclodextrin production was confirmed using thin layer chromatography. Six different starch substrates, namely, soluble starch, potato starch, sago starch, corn starch, corn flour, and rice flour, were tested for CD production. Raw potato starch granules were found to be the best substrate giving 13.46 gm/L of cyclodextrins after 1 h of incubation at 60°C. Raw sago starch gave 12.96 gm/L of cyclodextrins as the second best substrate. To achieve the maximum cyclodextrin production, statistical optimization using Central Composite Design (CCD) was carried out with three parameters, namely, potato starch concentration, CGTase enzyme concentration, and incubation temperature. Cyclodextrin production of 28.22 (gm/L) was achieved with the optimized parameters suggested by the model which are CGTase 4.8 U/L, starch 150 gm/L, and temperature 55.6°C. The suggested optimized conditions showed about 15% increase in ß-cyclodextrin production (28.22 gm/L) at 55.6°C as compared to 24.48 gm/L at 60°C. The degradation of raw potato starch granules by purified CGTase was also confirmed by microscopic observations.

Screening and Selection of Medium Components for Cyclodextrin Glucanotransferase Production by New Alkaliphile Microbacterium terrae KNR 9 Using Plackett-Burman Design.

Cyclodextrin glucanotransferase (CGTase, EC 2.4.1.19) production using new alkaliphile Microbacterium terrae KNR 9 was investigated by submerged fermentation. Statistical screening for components belonging to different categories, namely, soluble and raw starches as carbon sources, complex organic and inorganic nitrogen sources, minerals, a buffering agent, and a surfactant, has been carried out for CGTase production using Plackett-Burman factorial design. To screen out k (19), number of variables, k + 1 (20), number of experiments, were performed. Among the fourteen components screened, four components, namely, soluble starch, corn flour, yeast extract, and K2HPO4, were identified as significant with reference to their concentration effect and corresponding p value. Although soluble starch showed highest significance, comparable significance was also observed with corn flour and hence it was selected as a sole carbon source along with yeast extract and K2HPO4 for further media optimization studies. Using screened components, CGTase production was increased to 45% and 87% at shake flask level and laboratory scale fermenter, respectively, as compared to basal media.

Optimization and characterization of PHA from isolate Pannonibacter phragmitetus ERC8 using glycerol waste.

Polyhydroxyalkanoates (PHAs) have been considered as a good alternative for petrochemical based polymers due to its biodegradability. However, a high production cost limits their acceptance in industries. In present work, efforts have been made to optimize the production of PHA by Pannonibacter phragmitetus ERC8 using glycerol waste as a sole carbon source, with enhanced polymer production in a cost effective way. To check the possibility of growth and polymer accumulation potential of P. phragmitetus ERC8, various low cost substrates such as food waste, mutton tallow, whey, sugarcane bagasse, corn steep liquor and glycerol waste were used. Optimum concentration of selected factors obtained as response of statistical experimental design were 0.8% (v/v) glycerol waste, 0.26% (w/v) BHM and 1.25%OD as an inoculum for the maximum PHA production. The suggested model was validated and maximum 1.36 g/L of PHA production was obtained after 96 h. PHA production of 1.87 g/L was achieved in 5L (working volume 3 L) lab scale bioreactor with the suggested media components by RSM (Response Surface Methodology). Characterization of the PHA by NMR spectroscopy revealed that the polymer was a hetromonomer of (R)-3-hydroxybutyrate and medium chain length 3HA[(R)-3-hydroxyalkanoate] monomers.

A novel cyclodextrin glucanotransferase from an alkaliphile Microbacterium terrae KNR 9: purification and properties.

Cyclodextrin glucanotransferase (CGTase, EC. 2.1.1.19) produced using new alkaliphile Microbacterium terrae KNR 9 has been purified to homogeneity in a single step by the starch adsorption method. The specific activity of the purified CGTase was 45 U/mg compared to crude 0.9 U/mg. This resulted in a 50-fold purification of the enzyme with 33 % yield. The molecular weight of the purified enzyme was found to be 27.72 kDa as determined by SDS-PAGE. Non-denaturing gel electrophoresis and activity staining confirmed the presence of CGTase in crude and the ammonium sulfate precipitate fraction. The purified CGTase has a pI value of 4.2. The optimum pH of 6.0 and 60 °C temperature were found to be the best for CGTase activity. Purified CGTase showed 5.18 kcal/mol activation energy (Ea). The CGTase activity was increased in the presence of metal ions (5 mM): Ca+2 (130 %), Mg+2 (123 %), Mn+2 (119 %) and Co+2 (116 %). The enzyme activity was strongly inhibited in the presence of Hg+2 (0.0 %), Cu+2 (0.0 %) and Fe+2 (3.8 %). Inhibitor N-bromosuccinimide (5 mM) showed the highest 96 % inhibition of CGTase activity. SDS and triton X-100 among different detergents and surfactants (1.0 %, w/v) tested showed 92 % inhibition. Among the organic solvents checked for their effect on enzyme activity, 5 % (v/v) toluene resulted in 48 % increased activity. Polyethylene glycol-6000 showed a 26 % increase in the CGTase activity. The kinetic parameters K m and V max were 10 mg/ml and 146 µmol/mg min, respectively, for purified CGTase.

A statistical approach for the production of thermostable and alklophilic alpha-amylase from Bacillus amyloliquefaciens KCP2 under solid-state fermentation.

The bacterial strain producing thermostable, alklophilic alpha-amylase was identified as Bacillus amyloliquefaciens KCP2 using 16S rDNA gene sequencing data (NCBI Accession No: KF112071). Medium components were optimized through the statistical approach for the synthesis of alpha-amylase by the organism under solid-state fermentation using wheat bran as the substrate. The medium components influencing the enzyme production were identified using a two-level fractional factorial Plackett-Burman design. Among the various variables screened, starch, ammonium sulphate and calcium chloride were found to be most significant medium components. The optimum levels of these significant parameters were determined employing the response surface Central Composite design which significantly increased the enzyme production with the supplementation of starch 0.01 g, ammonium sulphate 0.2 g and 5 mM calcium chloride in the production medium. Temperature and pH stability of the alpha-amylase suggested its wide application in the food and pharmaceutical industries.

Kinetic and Thermodynamic Characterization of Glucoamylase from Colletotrichum sp. KCP1.

Extracellular glucoamylase of Colletotrichum sp. KCP1 produced through solid state fermentation was purified by two steps purification process comprising ammonium sulphate precipitation followed by gel permeation chromatography (GPC). The Recovery of glucoamylase after GPC was 50.40 % with 19.3-fold increase in specific activity. The molecular weight of enzyme was found to be 162.18 kDa by native-PAGE and was dimeric protein of two sub-units with molecular weight of 94.62 and 67.60 kDa as determined by SDS-PAGE. Activation energy for starch hydrolysis was 26.45 kJ mol(-1) while temperature quotient (Q 10 ) was found to be 1.9. The enzyme was found to be stable over wide pH range and thermally stable at 40-50 °C up to 120 min while exhibited maximum activity at 50 °C with pH 5.0. The pKa1 and pKa2 of ionisable groups of active site controlling V max were 3.5 and 6.8, respectively. V max , K m and K cat for starch hydrolysis were found to be 58.82 U ml(-1), 1.17 mg (starch) ml(-1) and 449 s(-1), respectively. Activation energy for irreversible inactivation (E a(d)) of glucoamylase was 74.85 kJ mol(-1). Thermodynamic parameters of irreversible inactivation of glucoamylase and starch hydrolysis were also determined.

Kinetic and thermodynamic characterization of lipase produced by Cellulomonas flavigena UNP3.

Lipase of Cellulomonas flavigena UNP3 was purified by two-step purification process comprising ammonium sulfate precipitation followed by gel permeation chromatography (GPC). The recovery of lipase after GPC was found to be 1.70% with 20.98-fold increase in specific activity. The molecular weight of lipase protein was found to be 45.2 kDa by SDS-PAGE. Activation energy for p-nitrophenol palmitate (pNPP) hydrolysis was 26.45 kJ mol(-1) , while temperature quotient (Q10 ) was found to be 1.64. The enzyme was found to be stable over wide pH range and thermally stable at 30-40 °C up to 60 min of incubation while exhibited maximum activity at 30 °C with pH 7.0. Vmax , Km , and Kcat for pNPP were found to be 666.71 U ml(-1) , 1.33 mM (pNPP) and 433 min(-1) , respectively. Activation energy for irreversible inactivation Ea(d) of lipase was 64.32 kJ mol(-1) . Thermodynamic parameters of irreversible inactivation of lipase and pNPP hydrolysis were also determined.

A novel method of single step hydrophobic interaction chromatography for the purification of phycocyanin from Phormidium fragile and its characterization for antioxidant property.

Phycocyanin--a major phycobiliprotein constitutively produced by many cyanobacteria--holds several promising applications in diagnostics, biomedical research, and therapeutics. This paper discusses a novel rapid method for the purification of cyanobacterial phycocyanin (C-PC) from Phormidium fragile using hydrophobic interaction chromatography. The protein was extracted and concentrated by grinding under liquid nitrogen and ammonium sulfate fractionation. C-PC was purified by single step hydrophobic interaction chromatography. Purified phycocyanin showed absorbance maximum (lambda(max)) at 624 nm. The criterion of purity (R) achieved was 4.52. Phycocyanin to phycoerythrin and phycocyanin to allophycocyanin purity ratio were 3.85 and 7.49, respectively. The purified protein showed a pI of 5.2 and has two subunits with molecular mass of 19 and 20 kDa each, corresponding to its highly reported alpha and beta subunits. The subunits of phycocyanin were confirmed by their bilin fluorescence using zinc assisted fluorescence enhancement technique. Intact C-PC was of 125 kDa as determined by HPLC, suggested the (alphabeta)(3) subunit assembly. Results obtained by this method in terms of purity, recovery, process time, simplicity, and efficacy are much better than previous methodologies. Purified phycocyanin was further scrutinized for its antioxidant capacity and judged against five non-enzymatic antioxidants by FRAP assay.

PHA-rubber blends: synthesis, characterization and biodegradation.

Medium chain length polyhydroxyalkanoates (mcl-PHA) and different rubbers; namely natural rubber, nitrile rubber and butadiene rubber were blended at room temperature using solution blending technique. Blends constituted 5%, 10% and 15% of mcl-PHA in different rubbers. Thermogravimetric analysis of mcl-PHA showed the melting temperature of the polymer around 50 degrees C. Thermal properties of the synthesized blend were studied by Differential Scanning Calorimetry which confirmed effective blending between the polymers. Blending of mcl-PHA with natural rubber led to the synthesis of a different polymer having the melting point of 90 degrees C. Degradation studies of the blends were carried out using a soil isolate, Pseudomonas sp. 202 for 30 days. Extracellular protein concentration as well as OD660 due to the growth of Pseudomonas sp. 202 was studied. The degradation of blended plastic material, as evidenced by % weight loss after degradation and increase in the growth of organism correlated with the amount of mcl-PHA present in the sample. Growth of Pseudomonas sp. 202 resulted in 14.63%, 16.12% and 3.84% weight loss of PHA:rubber blends (natural, nitrile and butadiene rubber). Scanning electron microscopic studies after 30 days of incubation further confirmed biodegradation of the films.

Statistical screening of medium components by Plackett-Burman design for lactic acid production by Lactobacillus sp. KCP01 using date juice.

Statistical screening of media components for production of lactic acid by Lactobacillus sp. KCP01 using date juice as a sugar source was carried out by Plackett-Burman design. Date juice at 5% sugar concentration when used alone showed 2.6 g/l of lactic acid production. Increase in lactic acid production (15.1 g/l) was observed with supplementation of salts and organic nitrogen sources of MRS medium and after optimization of pH and temperature using date juice as a C-source. Plackett-Burman design showed peptone, K2HPO4, sodium acetate and date juice as significant components influencing the lactic acid production.

Biosynthesis of medium chain length poly(3-hydroxyalkanoates) (mcl-PHAs) by Comamonas testosteroni during cultivation on vegetable oils.

Comamonas testosteroni has been studied for its ability to synthesize and accumulate medium chain length poly(3-hydroxyalkanoates) (mcl-PHAs) during cultivation on vegetable oils available in the local market. Castor seed oil, coconut oil, mustard oil, cotton seed oil, groundnut oil, olive oil and sesame oil were supplemented in the mineral medium as a sole source of carbon for growth and PHAs accumulation. The composition of PHAs was analysed by a coupled gas chromatography/mass spectroscopy (GC/MS). PHAs contained C6 to C14 3-hydroxy acids, with a strong presence of 3-hydroxyoctanoate when coconut oil, mustard oil, cotton seed oil and groundnut oil were supplied. 3-hydroxydecanoate was incorporated at higher concentrations when castor seed oil, olive oil and sesame oil were the substrates. Purified PHAs samples were characterized by Fourier Transform Infrared (FTIR) and 13C NMR analysis. During cultivation on various vegetable oils, C. testosteroni accumulated PHAs up to 78.5-87.5% of the cellular dry material (CDM). The efficiency of the culture to convert oil to PHAs ranged from 53.1% to 58.3% for different vegetable oils. Further more, the composition of the PHAs formed was not found to be substrate dependent as PHAs obtained from C. testosteroni during growth on variety of vegetable oils showed similar compositions; 3-hydroxyoctanoic acid and/or 3-hydroxydecanoic acid being always predominant. The polymerizing system of C. testosteroni showed higher preference for C8 and C10 monomers as longer and smaller monomers were incorporated less efficiently.