This study investigated unrecorded freshwater bacterial species in Korea. Water and sediment samples were collected from the Nakdong River basin from 2020-2022. Bacterial isolates obtained through the conventional culture method with commercial media were subjected to 16S rRNA gene sequencing to identify unrecorded bacterial species. Results of 16S rRNA gene sequencing of the bacterial isolates revealed that a total of 44 bacterial isolates shared 16S rRNA gene sequence similarities of more than 98.65%, with validly published bacterial species not reported in Korea yet. These isolates were phylogenetically assigned to 4 phyla, 7 classes, 21 orders, 33 families, and 42 genera. A total of 2, 6, 12, and 24 species belonged to phyla Bacillota, Bacteroidota, Actinomycetota, and Pseudomonadota, respectively. Here, we provide details of these 44 unrecorded bacterial species, including Gram staining, colony and cellular morphologies, biochemical properties, and phylogenetic position.

Large amounts of waste and wastewater from aquaculture have negatively impacted ecosystems. Among them, shrimp aquaculture wastewater contains large amounts of nitrogen contaminants derived from feed residues in an aerobic environment. This study isolated candidate strains from adult rockworms to treat shrimp aquaculture wastewater (SAW) in an aerobic environment. Among 87 strains isolated, 25 grew well at the same temperature as the shrimp aquaculture with excellent polymer degradation ability (>0.5 cm clear zone). Six isolates (strains AL1, AL4, AL5, AL6, LA10, and PR15) were finally selected after combining strains with excellent polymer degradation ability without antagonism. 16S rRNA sequencing analysis revealed that strains AL1, AL4, AL5, AL6, LA10, and PR15 were closely related to Bacillus paramycoides, Bacillus pumilus, Stenotrophomonas rhizophila, Bacillus paranthracis, Bacillus paranthracis, and Micrococcus luteus, respectively. When these six isolates were applied to SAW, they reached a maximum cell viability of 2.06×105 CFU mL-1. Their chemical oxygen demand (CODCr) and total nitrogen (TN) removal rates for 12 h were 51.0% and 44.6%, respectively, when the CODCr/TN ratio was approximately 10.0. Considering these removal rates achieved in this study under batch conditions, these six isolates could be used for aerobic denitrification. Consequently, these six isolates from rockworms are good candidates that can be applied to the field of aquaculture wastewater treatment.

A total of 31 bacterial strains were isolated from the Geum River basin in the Republic of Korea during our investigation of indigenous prokaryotic species. The isolated bacterial strains had high 16S rRNA gene sequence similarity (>98.7%) with those of validly published bacterial species, which have not been reported in Republic of Korea. The 31 bacterial strains were phylogenetically diverse and assigned to 4 phyla, 8 classes, 18 orders, 21 families, and 27 genera. At the genus level, the unreported species were affiliated with Kineococcus, Pedococcus, Rhodoluna, Salinibacterium, Rhodoluna, Arthrobacter, Williamsia, Nakamurella, Nocardioides of the class Actinobacteria, Patulibacter of the class Thermoleophilia, Pontibacter, Hymenobacter of the class Cytophagia, Flavobacterium of the class Flavobacteriia, Geomicrobium of the class Bacilli, Brevundimonas, Gellertiella, Rhizobium, Paracoccus, Taonella, Sphingomonas of the class Alphaproteobacteria, Burkholderia, Polaromonas, Hydrogenophaga, Chitinilyticum, Azospira, Zoogloea of the class Betaproteobacteria, and Pseudomonas of the class Gammaproteobacteria. The unreported bacterial species were further characterized by examining their morphological, cultural, physiological, and biochemical properties. The detailed descriptions of the 31 bacterial strains were provided.

Nine fish and one clam species were collected from freshwater environments in Korea, including four lakes, two streams, and the Nakdong River, to investigate the host-associated bacteria. Hundreds of bacterial strains were isolated from the samples using a cell sorter and a dilution plating method. After identification of the bacterial strains using 16S rRNA gene sequences, 42 strains with greater than 98.7% sequence similarity with validly published species were determined to be unrecorded bacterial species in Korea. These strains were phylogenetically diverse and assigned to four phyla, six classes, 17 orders, 27 families, and 32 genera. At the genus level, the unrecorded species were classified as Corynebacterium, Mycobacterium, Mycolicibacterium, Gordonia, Williamsia, Modestobacter, Brachybacterium, Sanquibacter, Arthrobacter, and Mycolicibacterium of the class Actinobacteria; Empedobacter, and Flavobacterium of the class Flavobacteriia; Fictibacillus, Psychrobacillus, Cohnella, Paenibacillus, Rummeliibacillus, Enterococcus, and Vagococcus of the class Bacilli; Aquamicrobium, Paracoccus, and Sphingomonas of the class Alphaproteobacteria; Achromobacter, Delftia, and Deefgea of the class Betaproteobacteria; and Aeromonas, Providencia, Yersinia, Marinomonas, Acinetobacter, and Pseudomonas of the class Gammaproteobacteria. The 42 unrecorded species were subjected to further taxonomic characterization using gram staining, cellular and colony morphological determination, biochemical analyses, and phylogenetic analyses. This paper provides detailed descriptions of the 42 previously unrecorded bacterial species.

Ostrea denselamellosa and Eriocheir japonica samples were collected from the Seomjin River in 2019 as part of the “Research of Host-Associated Bacteria” research program. Almost 200 bacterial strains were isolated from the O. denselamellosa and E. japonica samples and subsequently identified by 16S rRNA gene sequencing. Among the bacterial isolates, ten strains possessed greater than 98.7% sequence similarity with published bacterial species that had not previously been recorded in Korea. These species were phylogenetically diverse, belonging to three phyla, four classes, seven orders, and eight genera. At the genus and class level, the previously unrecorded species belonged to Pseudoalteromonas, Aliivibrio, Rheinheimera, Leucothrix, and Shewanella of the class Gamma-proteobacteria, Olleya of the class Flavobacteriia, Algoriphagus of the class Cytophagia, and Lactococcus of the class Bacilli. The previously unrecorded species were further characterized by examining their Gram staining, colony and cell morphology, biochemical properties, and phylogenetic positions.

슈퍼요소를 이용한 구조해석은 항공기나 선박 둥 대형구조물의 해석에서 장점올 가지며 하드웨어의 제한된 조건속에서 효과적인 결과를 준다. 본 논문에서는 고정된 타이벡 (tie back) 상태에서 세계 최대의 5α삐톤， 회전 상태에서 3α%톤올 들어 올릴 수 있는 크레인선의 구조 안전성 검토를 위하여 슈퍼요소로 분할된 부분 구조물 해석을 다루었으며， 효과적인 부분구조화 (substructuring) 과정과 독특한 하중추출방법 및 유한요소 모델링 기법을 제시하고 있다. 또한 해 석결과에 근거한 실질적인 구조물의 총괄적 국부보강방법올 보여주고 있다. 대형 크레인선의 구조해석적용 연구를 통하여 부분구조기법의 효율성을 확립하였으며 이러한 해석기법을 통하여 새로운 형태의 유사한 구조물에 대한 해석지침을 제시하고 었다.

Tuberculosis (TB) is still a significant public health problem in Korea. In many cases, it is not easy to diagnose TB. A 13-year-old male patient was admitted for left chest pain for 6 months period. Chest radiography done two months ago during the school screening revealed a pleural effusion in the left lung. All cultures were negative, and 3 sputum samples and his pleural fluid sample tested negative for Acid-fast bacilli. There was no evidence of a malignant effusion. A pleural fluid examination revealed features suggestive of an empyema. Thick and yellowish pus was drawn out. Pleural fluid analysis presented White blood cell 5,200/mm3, and neutrophil-dominant with 60% of neutrophil. In an effort to attain a diagnosis, a video-assisted thoracoscopy procedure was performed with pleural drainage and biopsies. Active chronic granulomatous pleuritis was found through pleural biopsies. He was responsive to treatment and received 6 months of anti-TB therapy with complete clinical resolution. If the clinical picture is in confusion, pleural biopsy is occasionally indicated to diagnose TB pleuritis.

The mode of inheritance and allelic relationship of resistance genes in a Korean landrace, Guju and a Korean weedy rice, Geumleungaengmi 33 were studied using Korean isolate (HB9101, race K1) of Xanthomonas oryzae pv. oryzae. The analysis of F₁

콩의 건물축적과 단백질전류에 대한 Source-Sink변경의 효과를 구명하기 위하여 1992년에 고려대학교 자연자원대학 실험농장에서 황금콩을 공시품종으로 착협시기(R3)에 상위 40%, 하위 60%의 엽과 협을 제거하여 건물중 및 단백질함량의 변화를 조사한 결과는 다음과 같다. 1. 상엽-하협제거처리에서 하위 엽과 경 건물중이 증가하였고, 상위 종실과 협 건물중은 감소하였다. 2. 엽의 단백질함량은 상위 엽보다 하위 엽에서 높았다. 3. 종실의 단백질함량은 상엽-하협제거와 하엽-상협제거처리에서 낮았다. 4. 상엽-하협제거처리에서 엽의 단백질함량은 가장 높았고 종실 단백질함량은 가장 낮았다. 5. 본 실험의 결과에서 콩의 단백질원은 하부에서 상부로 이동하나 생식생장기간중의 장거리 전류를 위한 엽 단백질의 재이동은 약한 것으로 나타났다.