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Hydrolytic degradation of polylactides (PLAs) bearing cinnamic acid derivatives was conducted and their thermal degradation temperature at 10% weight loss (T10) and melting point temperature (Tm) were measured, to confirm that a PLA stereocomplex could be modified for use in a wide range of application. The improved T10 values of PLA films by chain end modification were maintained after the alkaline degradation. The increase in Tm by stereocomplex formation was also maintained after degradation with a slight change in the melting point of the attached homopolymer. The present results indicate the suitability of chain end modification for the additional functionality of PLA stereocomplex films. [ABSTRACT FROM AUTHOR]

The pathogenic characteristics of Bacillus thuringiensis and Bacillus cereus were analyzed by the cloning and amino acid sequencing of toxin genes from Bacillus cereus FM1 strain and Bacillus thuringiensis israelensis. Analysis of the enterotoxin genes from the two Bacillus species indicated the presence of beta structures and consecutive Asn residues. Furthermore, the nucleotide sequences of the enterotoxin genes are similar in both Bacillus thuringiensis and Bacillus cereus.

The cloning and expression of two crystal protein genes, cry44Aalorf2-44A and cry30Balorf2-30B was reported from Bacillus thuringiensis subsp. entomocidus INA288. These studies serve as evidence that genes from INA288, such as cry44Aalorf2-44A is useful in managing resistance and as a component of synthetic combinations of mosquitocidal toxins.

To infect their hosts, DNA viruses must successfully initiate the expression of viral genes that control subsequent viral gene expression and manipulate the host environment. Viral genes that are immediately expressed upon infection play critical roles in the early infection process. In this study, we investigated the expression and regulation of five canonical regulatory immediate-early (IE) genes of Autographa californica multicapsid nucleopolyhedrovirus: ie0, ie1, ie2, me53, and pe38. A systematic transient gene-expression analysis revealed that these IE genes are generally transactivators, suggesting the existence of a highly interactive regulatory network. A genetic analysis using gene knockout viruses demonstrated that the expression of these IE genes was tolerant to the single deletions of activator IE genes in the early stage of infection. A network graph analysis on the regulatory relationships observed in the transient expression analysis suggested that the robustness of IE gene expression is due to the organization of the IE gene regulatory network and how each IE gene is activated. However, some regulatory relationships detected by the genetic analysis were contradictory to those observed in the transient expression analysis, especially for IE0-mediated regulation. Statistical modeling, combined with genetic analysis using knockout alleles for ie0 and ie1, showed that the repressor function of ie0 was due to the interaction between ie0 and ie1, not ie0 itself. Taken together, these systematic approaches provided insight into the topology and nature of the IE gene regulatory network. [ABSTRACT FROM AUTHOR]

The article studies the phylogenetic relationship of Paenibacillus (P.) species and analysis of an yheCD-like sequence found in replication origin region. The study found that in the rsmG-gyrA region, gene arrangements in Paenibacillus species were identical to those of Bacillus species except an open reading frame (orfl4) positioned between gyrB and gyrA. The phylogenetic tree suggested that P. popilliae, P. thiaminolyticus, and P. dendritiformis were closely related species.

The article discusses a study which reports the draft genome sequence of Paenibacillus popilliae, a rod-shaped endospore-forming bacterium, which causes milky disease in Japanese beetle Popillia japonica and related species. Topics discussed include preparation of the bacterial culture to extract genomic DNA from bacterial cells, phylogenetic analysis using previous data sets on microbial population, and comparison of the analysis with other entomo-pathogenic bacteria.

The article discusses a study which reports the draft genome sequence of Paenibacillus popilliae, a rod-shaped endospore-forming bacterium, which causes milky disease in Japanese beetle Popillia japonica and related species. Topics discussed include preparation of the bacterial culture to extract genomic DNA from bacterial cells, phylogenetic analysis using previous data sets on microbial population, and comparison of the analysis with other entomo-pathogenic bacteria.

In 2005, natural epizootics were observed during an outbreak of Setothosea asigna (Lepidoptera: Limacodidae) larvae in an oil palm plantation in South Sumatra, Indonesia. The causative agent was filterable, which implied it was a virus. Since preliminary testing using reverse PCA gave a positive result for the Thosea asigna virus (TaV), we experimented with the purification of the viral agent from the diseased larvae. Electron microscopy revealed nonenveloped virus-like particles that were spherical in shape and about 40 nm in diameter. eDNA cloning followed by sequencing demonstrated that RNA purified from the particles contained two large openreading- frames (OAFs) with a partly shared sequence and extensive homology (> 98% identity at the nucleotide level) with OAFs of TaV encoding an RNA-dependent RNA polymerase and the capsid protein, respectively. 3' RACE suggested that there is, like in TaV genomic RNA, no poly(A) tract at the 3'-terminus of the RNA. The pathogenicity of the purified particles against Limacodidae larvae in Japan was demonstrated to be very strong for Monema f/avescens and Austrapoda dentata. These results indicated that the agent causing the epizootic disease among S. asigna larvae in the oil palm plantations was TaV which also has potential as a biological control agent for Limacodidae pests in Japan. [ABSTRACT FROM AUTHOR]

A fiber heterodyne interferometer probe free from external disturbance, which can measure small displacement of an object as a pressure transducer or a vibrational object, is described. The phase fluctuation in the fiber due to external disturbance is excluded using a reference beat signal of light beams from a reflection mirror on a graded index rod lens. A graded index-type multimode fiber connected to one end of a single-mode fiber by arc fusion splicing is used to improve acceptance of the light. The characteristics of the fiber probe are also described. [ABSTRACT FROM AUTHOR]

The article discusses the role of Cry2Aa prgene in Bacillus thuringiensis and informs that the protoxin synthesized kills Bombyx mori and Lymantria dispar larvae. The killing mechanism of Cry2Aa toxin includes solubiliization and purification of the Cry2Aa protoxin, digestion of Cry2Aa protoxin with midgut fluid and digestion of Cry2Aa protoxin with chymotrypsin. The linkage between peptides 49Tyr/Val50 and 145Lys/Ser146 is hydrolyzed by chymotrypsin.

The Cry1Fa insecticidal protein from Bacillus thuringiensis (Bt) was expressed on the surface of Bacillus subtilis (Bs) spores to create transgenic Bs spores referred to as Spore-Cry1Fa. Cry1Fa, along with its leader sequence, was connected to the carboxyl end of a Bs spore outercoat protein, CotC, through a flexible linker. The Arg-27 residue of the Cry1Fa protein was mutated to Leu to prevent detachment from the spores due to protease digestion. The expression of the Cry protein on the Bs spores was confirmed by fluorescence microscopy using an anti-Cry1Fa antibody. The Cry protein, tightly anchored to the spore surface, appeared to be functional in terms of receptor binding. Spore-Cry1Fa bound to Sf9 cells expressing Spodoptera frugiperda (Sf) ABCC2 transporter and killed the cells within 60 min. Additionally, nano-lipid particles of SfABCC2 were produced using styrene-maleic acid (SMA) to demonstrate the binding to Spore-Cry1Fa., Competing Interests: Conflicts of interest and acknowledgmentsThis study was financially supported by a grant from Syngenta Crop Protection LLC to Hokkaido University. Syngenta and Hokkaido University co-own the intellectual property resulting from this study and have jointly filed a patent application related to this study. There are no other conflicts of interest. SK conducted most of the experiments under the direct supervision of SA who also contributed to specific experiments such as baculovirus-mediated cloning of transporter genes into the Sf9 cell. PO played a significant role in leading the overall research direction and developing experimental designs. TY conceived the ideas of extracting ABCC2 using SMA and applying spore display technology to Bt Cry proteins including the vector design. We would like to express our gratitude to Syngenta scientists Matt Bramlett, Eric Chen, Chris Fleming, Mike Reynolds and Jun Zhang for their input and support throughout the project including their critical review of the manuscript., (© 2024 Pesticide Science Society of Japan.)

The δ-endotoxin Cry4Aa from Bacillus thuringiensis israelensis (Bti) has insecticidal characteristics specific to insects of the order Diptera. Although Cry4Aa has shown potential as an effective proteinaceous pesticide against mosquitoes, it has an ultraviolet (UV)-intolerant property that limits its outdoor use. Our previous research showed that protein microcrystal polyhedra from Bombyx mori cypovirus can encapsulate diverse foreign proteins and maintain long-term protein activity under hostile environmental conditions, including UV irradiation. In this study, we report the development of polyhedra encapsulating the Cry4Aa insecticidal activity domain by using a modified baculovirus expression system. We confirmed the oral intake of recombinant polyhedra introduced into the experimental environment by the larvae of a mosquito, Aedes albopictus, and delivery of encapsulated proteins into the digestive tract. The polyhedra encapsulating partial Cry4Aa showed mosquito larvicidal activity during incubation of larvae with 50% lethal-dose value of 23.717×104 cubes for 10 Aedes albopictus larvae in 1 ml water. In addition, polyhedra showed a specific property to reduce the impact of UV-C irradiation on the activity of encapsulated partial Cry4Aa, thus demonstrating the effectiveness of encapsulating Bti δ-endotoxins inside polyhedra to increase the availability of proteinaceous pesticides for outdoor use for mosquito control., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2022. Published by The Company of Biologists Ltd.)

Objective: To determine the cytotoxicity of the crude culture broth containing enterotoxins of B. cereus and investigate the nucleotide sequences of ent FM among various isolates B. cereus., Material and Method: The 1.2 kb fragment of ent FM of B. cereus was amplified, cloned, sequenced, and compared with published sequences. The biological activity of crude culture broth containing enterotoxins with and without monoclonal antibodies against HBL, NHE, and EntFM enterotoxins was tested using Vero cells assay., Results: A percentage homology of nucleotide sequences and deduced amino acid sequences among test isolates and published strains were 90-99% and 88-99%, respectively. An assays for cytotoxic activity revealed that seven and three of B. cereus isolates were positive for NHE enterotoxin and EntFM enterotoxin, respectively. In addition, the 4-repeating sequences "TCAAAC" of ent FM were found, which may or may not be probably correlated with cytotoxicity of B. cereus., Conclusion: The enterotoxin FM from B. cereus isolates is cytotoxic and the degree of cytotoxicity depends on the bacterial strain.

We previously reported that a novel hydrophilic gamma-tocopherol (gamma-Toc) derivative, gamma-tocopheryl-N,N-dimethylglycinate hydrochloride (gamma-TDMG) gets converted to the antioxidant gamma-Toc in skin. We also found that this derivative displayed greater bioavailability than gamma-Toc itself. In the present study, we determined whether gamma-TDMG could reduce UV-induced skin pigmentation in brownish guinea pigs. gamma-TDMG (0.1 or 0.5%) was topically applied to the skin before and after it was exposed to UVB plus UVA (3 times/week for 1 week), and then 10 times/week for 4 weeks thereafter. Treatment with 0.5% gamma-TDMG resulted in significant skin lightening (70% of the pigmentation of irradiated controls). We also found that melanin synthesis was dose-dependently inhibited by gamma-TDMG in murine B16 melanoma cells. When gamma-TDMG or kojic acid (250 microM) were added to homogenates of B16 melanoma cells, their tyrosinase activity was significantly inhibited by approximately 40% and 75%, respectively. Mushroom tyrosinase activity was significantly inhibited by 200 microM gamma-Toc and kojic acid, but not gamma-TDMG. When B16 cells were incubated with 250 microM gamma-TDMG for 24 or 48 h, their intracellular gamma-Toc concentrations rose over 100 fold to 10.5 and 11.2 nmol/10(6) cells, respectively, suggesting that gamma-TDMG was rapidly converted to gamma-Toc in these cells and that their reduced melanin synthesis may have been due to the activity of gamma-Toc. Our data further suggest that the topical application of gamma-TDMG may be efficacious in preventing photo-induced skin pigmentation in humans.

A survey of proliferative enteritis (PE) in pigs at a meat processing plant was conducted using polymerase chain reaction (PCR) testing methods. During the investigation period, 227 of 83,717 pigs brought to the meat processing plant from Iwate, Fukushima, Miyagi, Niigata, and Yamagata Prefectures displayed characteristic general pathological features in terminal ileum, including mucosal hypertrophy and reticulation of serosal surface. Of these, 179 cases were further examined in the laboratory. All cases displayed characteristic histopathological features, and the specific band of the Lawsonia intracellularis (Li) causative agent of PE in pigs was detected in 155 cases by PCR testing methods. These results suggested a general infiltration of Li in the Tohoku district.