Entomopathogenic fungi have been studied to develop for biological control agents as an alternative to chemical control agents in insect pest management. Two Lepidopteran insects, Spodoptera exigua and Plutella xylostella, are serious insect pests infest various crops, but not effectively controlled by commercial chemical pesticides due to its high insecticide resistance. A fungal isolate was isolated from S. exigua larvae collected from green onion field in Andong, Korea. To identify the fungal isolate, 18srRNA sequence for internal transcribed spacer (ITS) and β-tubulin regions were sequenced. The ITS and β-tubulin sequence were highly matched to Beauveria bassiana and morphological characteristics also was fit to known B. bassiana. Finally, isolated fungus has identified as B. bassiana and named B. bassiana ANU1. The result of bioassay, median lethal concentrations were 2.7×103 and 0.9×103 conidia/ml and medial lethal times were 65.6 and 60.8 h to S. exigua and P. xylostella, respectively. B. bassiana ANU1 showed high pathogenicity to two insect pests from 20℃ to 30℃ at 50% relative humidity (RH) and more than 40% RH at 25℃ with 107 conidia/ml of concentration.

A xylan-decomposing Gram-positive bacterium, Cellulosimicrobium cellulans DY-8, was isolated from the gut of a wood-feeding longicorn beetle, Moechotypa diphysis. To amplify a partial fragment of the GH 10 β-1,4- xylanase (XylC) gene of strain DY-8, two degenerated oligonucleotide primers were designed based on strictly conserved regions (WDVVNE and ITELLDV) in the GH family 10 xylanolytic enzymes. The full gene (1488-bp) of XylC, which was predicted to encode a protein consisting of 495 amino acids with a molecular mass of 52.0 kDa and a calculated pI of 6.49, was cloned by repeated DNA walking and nested PCR protocols. The results of a protein blast survey showed that XylC was a β -1,4-xylanase comprised of an N-terminal catalytic GH10 domain (from Ser48 to Leu338) and a C-terminal RICIN domain (from Tyr359 to Leu492). This overall structure of XylC was 57% identical to that of Actinoplanes sp. SE50/110 β -1,4-xylanase (Accession number: YP_006265966), which has not yet been biochemically characterized.

A xylanolytic microorganism, strain DY-7, was isolated from the gut of the mole cricket, Gryllotalpa orientalis. The result of phylogenetic analysis based on its 16S rDNA sequence revealed that the isolate was a Gram-positive bacterium belonging to the genus Streptomyces. The cloned gene (1350-bp) encoding a GH family 10 β -1,4-xylanase (XylA) from Streptomyces sp. strain DY-7 was overexpressed in Escherichia coli BL21 and its gene products were characterized. The hydrolysis activities of rXylA and rXylAΔCBD II against xylosidic materials were maximum at pH 5.5 and 65oC. However, deletion of CBD II in the C-terminus region of XylA significantly increased the thermal stability of the enzyme at high temperatures above 50oC. The xylanolytic activity of rXylA was slightly enhanced in the presence of 1 mM Mn2+ and 5 mM sodium azide but it was completely inactivated by 1 mM Hg2+ and 5 mM N-bromosuccinimide. rXylA was capable of efficiently decomposing various xylosidic compounds, PNP-cellobioside, and PNP-xylopyranoside, whereas other hexose-based compounds were insensitive to the enzyme. The specific activities of rXylA toward oat spelts xylan and PNP-cellobioside were 649.8 U/mg and 328.1 U/mg, respectively. Enzymatic degradation of birchwood xylan and xylooligosaccharides (xylotriose to xylohexaose) resulted in the production of xylobiose (>75%) as the main hydrolysis product together with a small amount (4%<) of xylose as the final hydrolysis product.

The purpose of this study is to identify the level of masseter muscle tension according to the levels of restricted movement and pain in the temporomandibular joint(TMJ), thereby verifying the fact that excessive masseter muscle tension can be a cause for restricted movement and pain in the TMJ. The subjects of this study were 81 men and women in their 20s and 30s, who feel uncomfortable with their masticatory function on the preferred chewing side. The subjects were measured in terms of the range of motion (ROM) and deviation of the TMJ and the degree of pain in the affected region. The ROM and deviation of the TMJ were measured using the Global Posture System(GPS) after instructing each subject to open his/her mouth to the fullest and taking photos of the subject with a digital camera. The tension of the masseter muscle was measured with a Pressure Threshold Meter(PTM). After the measurements, in order to compare the ROM of the TMJ, the subjects were divided into two groups based on the ROM of above 35mm and below 35mm. For the deviation and pain, based on the average of total subjects, the subjects were divided into two groups of above and below average. Thereafter, the levels of masseter muscle tension were compared between each pair of groups. According to the results, when each variable was compared between the respective two groups, in terms of the deviation, the pressure pain threshold(PPT) of the masseter muscle revealed a statistically significant difference(p<.05). However, the ROM and pain showed no statistically significant difference. Consequently, masseter muscle tension may cause restricted movement in the TMJ. In particular, the deviation and tension in the masseter muscle is considered to be a factor that causes deviation in the TMJ.

The two-spotted spider mite Tetranychus urticae is a worldwide crop pest with a high insecticide resistance and an extensive host range. The aim of the present study was to evaluate the effect of PaeciPora®, which was formulated from the aerial conidia of an entomopathogenic fungus Paecilomyces lilacinus strain HY-4, to control T. urticae in cucumber field. In the field study, conidia of P. lilacinus HY-4 and a chemical acaricide azocyclotin were investigated for their control of the adult females of T. urticae. The strain produced a mortality of 56.0% on day 3 and 63.6% on day 7 post-treatment respectively at 1×107 conidia/mL, and no evidence of a mortality benefit was seen in the control group. Additionally, in the pesticide injury test, no agrochemical damage was found in hot pepper, watermelon, Chinese cabbage, oriental melon or strawberry by spraying PaeciPora® on them. The results indicated the possibility of the use of P. lilacinus HY-4 as a microbiological control agent against T. urticae in the Integrated Pest Management program.

An entomopathogenic filamentous fungus, Paecilomyces lilacinus strain HY-4, has a great potential as a promising bio-pesticide due to its superior pathogenicity against Adoretus tenuimaculatus and Tetranychus urticae. When the fungal strain infects host cuticle, it secrets a combination of hydrolytic enzymes including chitinase to solubilize the cuticle. Thus, we investigated effects of different carbon and nitrogen sources on the production of a chitinase from P. lilacinus strain HY-4. The organism produced an extracellular chitinase at a relatively high level (45.4 mU/ml) when cultivated for 5 days on a medium supplemented with insect pupa (0.5%) and colloidal chitin (1%), which was prepared by treating chitin from crab shells (Sigma-Aldrich Co. Ltd.) with 12 N HCl solution. However, extracellular secretion of chitinase by strain HY-4 was found to be significantly repressed in the presence of glucose (1%).

The extracellular GH11 β-1,4-xylanase (XylY) gene (633-bp) of Paenibacillus sp. strain KYJ-16 was molecularly cloned by repeated DNA walking and nested PCR method. The xylY gene was predicted to encode an extracellular protein consisting of 611 amino acids with a nesuced molecular mass of 23 kDa and a calculated pI of 9.55. Protein blast search revealed that the enzyme consisted of a putative catalytic domain, which is homologous to a catalytic GH11 domain. The highest sequence identity (92%) was obtained as the catalytic GH11 domain of XylY was compared to that of Paenibacillus sp. strain HGF5 (GenBank accession number: EGG35584) that has not yet been characterized. Enzymatic properties of the recombinant His-tagged enzyme (rXylY) overexpressed in E. coli BL21 harboring pET-28a(+)/xylY will be also presented.

The gene (2,304-bp) encoding a novel xylanolytic enzyme (XylD) with a catalytic domain, which is 70% identical to that of Cellulomonas flavigena DSM 20109 GH6 β-1,4-cellobiohydrolase, was identified from an earthworm (Eisenia fetida)-symbiotic bacterium, Cellulosimicrobium sp. strain HY-13. The enzyme consisted of an N-terminal catalytic GH6-like domain, a fibronectin type 3 (Fn3) domain, and a C-terminal carbohydrate-binding module 2 (CBM 2). XylDΔFn3-CBM 2 displayed high transferase activity (788.3 IU mg-1) toward p-nitrophenyl (PNP) cellobioside, but did not degrade xylobiose, glucose-based materials, or other PNP-sugar derivatives. Birchwood xylan was degraded by XylDΔFn3-CBM 2 to xylobiose (59.2%) and xylotriose (40.8%). The transglycosylation activity of the enzyme, which enabled the formation of xylobiose (33.6%) and xylotriose (66.4%) from the hydrolysis of xylotriose, indicates that it is not an inverting enzyme but a retaining enzyme. The endo-β-1,4-xylanase activity of XylDΔFn3-CBM 2 increased significantly by approximately 2.0-fold in the presence of 50 mM xylobiose.