• BMB Reports
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• 제57권1호
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• pp.40-49
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• 2024

Prokaryotes encode clustered regularly interspaced short palindromic repeat (CRISPR) arrays and CRISPR-associated (Cas) genes as an adaptive immune machinery. CRISPR-Cas systems effectively protect hosts from the invasion of foreign enemies, such as bacteriophages and plasmids. During a process called 'adaptation', non-self-nucleic acid fragments are acquired as spacers between repeats in the host CRISPR array, to establish immunological memory. The highly conserved Cas1-Cas2 complexes function as molecular recorders to integrate spacers in a time course manner, which can subsequently be expressed as crRNAs complexed with Cas effector proteins for the RNA-guided interference pathways. In some of the RNA-targeting type III systems, Cas1 proteins are fused with reverse transcriptase (RT), indicating that RT-Cas1-Cas2 complexes can acquire RNA transcripts for spacer acquisition. In this review, we summarize current studies that focus on the molecular structure and function of the RT-fused Cas1-Cas2 integrase, and its potential applications as a directional RNA-recording tool in cells. Furthermore, we highlight outstanding questions for RT-Cas1-Cas2 studies and future directions for RNA-recording CRISPR technologies.

• 대한화장품학회지
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• 제18권1호
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• pp.42-63
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• 1992

방부제와 계면활성제를 혼합 사용하였을 경우 미생물에 대한 방부력 변화를 검토하고자 Imidazolidinyl urea, Methylparaben, Imidazolidinyl urea와 Methylparaben 혼합체 3종의 농도에 따른 각 농도별 계면활성제 Tween 20, Tween60, Tween 80의 첨가가 S. aureus ATCC E. coli ATCC 10536, P. aeruginosa NCTC 10490에 대한 방부력에 미치는 영향을 실험하였으며, 아울러 제품내에서 Tween 60 계면활성제 농도에 변화를 주었을 때의 방부력 변화를 조사하였다. 1. S. aureus ATCC 6538 Methylparaben과 Imidazolidinyl urea 혼합체에 대해 내성을 전혀 갖지 않았다. 2. E. coli ATCC 10536은 Mithylparaben에 대하여 내성을 전혀 갖지 않았다. 3. Mithlparaben과 Imidazolidinyl urea 혼합체는 Gram 음성균, Gram 양성균에 넓은 향균 spectrum을 나타났다. 즉, 방부제는 단일 사용시보다 혼합 사용시 상승효과를 가졌다. 4. Imidazolidinyl urea는 Polyoxyethylene(20) Sorbitan fatty acid ester류에 의해 전혀 방부력에 영향을 받지 않는 반면에 시험균주 3종에 대해 내성이 잘 되었다. 5. Muthylparaben은 Polyoxyethylene(20) Sorbitan fatty acid ester류에 의해 불활성화가 큰 폭으로 나타났다. 6. 방부제 Methyparaben 0.2%를 함유하는 제품에 비이온 계면활성제 Tween 60의 량을 0.5, 1.0, 2.0%로 달리 첨가하였을시 D-value는 제품내 비이온 계면활성제 Tween 60의 량이 증가할수록 비례하여 커졌다. 즉, 비이온 계면활성제 Polyoxyethylene(20) Sorbitan monostearate에 의해 Methylparaben이 제품내에서도 불활성화 되었다.

• 한국육종학회지
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• 제42권5호
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• pp.455-462
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• 2010

Purple acid phosphatase is important for phosphorus remobilization in plants, but its role in plant adaptation to low phosphorus availability is not known. The cDNA encoding O. sativa purple acid phosphatase (OsPAP1) has 1008 bp with an open reading frame of 335 amino acid residues. The amino acid sequence of OsPAP1 cDNA shows of 50-51% identity with other plant purple acid phosphatases. OsPAP1 was expressed in rice plants and in cell cultures in the absence of phosphate ($P_i$). The expression was organ-specific with the strongest expression in $P_i$-deprived roots. Functional expression of the OsPAP1 gene in the transgenic Arabidopsis line was confirmed by northern and western blot analysis. OsPAP1 overexpression lines had higher phosphatase activity than wild-type. Overexpression of OsPAP1 in Arabidopsis plants resulted in increased Pi accumulation under Pi sufficient condition. These results show that the OsPAP1 gene represents more efficient $P_i$ uptake and can be used to develop new transgenic dicotyledonous plants.

• 한국식품영양과학회지
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• 제45권4호
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• pp.577-584
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• 2016

다양한 환경에서 분리된 시가독소 생산성 대장균(Shiga toxin-producing E. coli, STEC, n=18)을 초산혼합용액(AAS;400 mM, pH 3.2, $30^{\circ}C$)에 노출한 후 산 저항성을 측정하였다. 또한, 선정된 4종류의 non-O157:H7 STEC균을 사과주스, 파인애플주스, 오렌지주스, 딸기주스(pH 3.8)에 정봉하여 $4^{\circ}C$와 $20^{\circ}C$에서 24시간 산 적응시킨 후 위합성용액(SGF, pH 1.5)에서 2시간 동안 생존능력을 평가하였다. Non-O157:H7 STEC를 AAS에 노출했을 때 O111 혈청형의 STEC는 평균 0.12 log CFU/mL 감소하여 다른 혈청형에 비하여 가장 강한 산 저항성을 나타냈고 O157:H7 STEC와 유의적 차이가 없었으며(P>0.05), O26 혈청형의 STEC는 가장 민감한 것으로 나타났다. 반면, AAS에 glutamic acid를 첨가하였을 경우 모든 STEC는 혈청형과 관계없이 초산에 매우 강한 저항성을 나타내었다(P>0.05). SGF에서 생존능력을 측정한 결과, 06E0218(O157:H7)은 다른 non-O157:H7 STEC 균들보다 생존능력이 낮았고 03-4669(O145:NM)가 가장 강한 생존능력을 나타내었다. 한편, 과일주스 중에서는 파인애플주스에 산 적응된 STEC가 SGF에 가장 강한 생존능력을 나타내었다. $4^{\circ}C$의 과일주스에 STEC를 산 적응시켰을 경우 $20^{\circ}C$보다 SGF에 대한 생존능력이 현저하게 높았다(P<0.05). 따라서 과일주스에 의한 non-O157:H7 STEC의 산 적응력 증가는 위장관 내 생존율 및 식중독 발생을 높일 수 있으므로 이에 대한 적절한 연구와 안전관리 옵션을 제공할 필요가 있을 것으로 판단된다.

• Animal Bioscience
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• 제35권7호
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• pp.1069-1079
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• 2022

Objective: The objective of this study was to investigate the effect of 4-month intensive feeding on the meat quality, fatty acid profile, flavor, and growth performance of grazing Hulunbuir sheep (HBS). Methods: The HBS were selected 4-months after birth in a pasture rearing system as the experimental animals (n = 44, female, average body weight 23.8±2.2 kg) then divided equally into pasture-based grazing fattening (PAS) and concentrate-included intensive fattening (CON) groups for another 4-month finishing. When finished fattening, all animals were slaughtered to collect musculus longissimus dorsi subcutaneous adipose tissue and to investigate the influences on meat quality, fatty acid profile, flavor and growth performance. Results: The results showed lambs in CON group got significantly higher live weight, hot carcass weight, and dressing percentage. The CON group had significantly higher value of redness (a^*), lightness (L^*) and water holding capacity (p<0.05), significantly lower value of Warner-Bratzler shear force than the PAS group (p<0.05). The subcutaneous fat from CON group lambs demonstrated a significantly higher content of C18:1 and C18:2 (p<0.05), but lower C14:0 and C16:0, indicating an increased degree of unsaturated fatty acid. The content of 4-methyloctanoic acid, 4-ethyloctanoic acid and 4-methylnonanoic acid had increased 2 to 4 times, representing a more intense odor in the CON group. However, the values were still lower than most sheep breeds reported, indicating the indoor feeding system could not fundamentally deteriorate the excellent meat characteristic of HBS. Conclusion: It was evident that lambs in CON group exhibited a better meat production performance, improved in meat color, texture and healthier fatty acid profile through pasture-weaned concentrate included intensive fattening system, which offers a good alternative regimen for lamb finishing and has a wide prospection in the HBS meat industry.

• Asian-Australasian Journal of Animal Sciences
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• 제11권4호
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• pp.434-440
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• 1998

Seven hybrid lines of Leucaena leucocephala $\times$ L. diversifolia and two control lines of L. leucocephala were compared for their adaptation to acid-soils and tolerance to damage by the psyllid, Heteropsyla cubana, at four locations over two years in Peninsular Malaysia. Primary data on leaf composition and in vitro digestibility (nutrition variables) and secondary data on plant height, stem girth and psyllid damage (agronomy variables) were the measures of performance. Cluster solutions of the nine lines were different within locations, between locations and between years for nutrition and agronomy variables. Controls and hybrids did not cluster separately. Principal component scores of the nine lines gave rank orders which were different by location and by year. No performance trend could be detected between hybrids and controls. The conclusion is that nutritional and agronomic characteristics in Leucaena are independent, soil composition and weather did not consistently affect performance, and evidence is inconclusive as to the benefits of interspecific crossing with L. diversifolia.

• 미생물학회지
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• 제38권1호
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• pp.45-49
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• 2002

Bradyrhizobium japonicum 은 콩과 식물의 뿌리에 감염하여 뿌리흑을 형성 질소를 고정하는 독특한 능력을 갖는 토양 세균이며 미생물 비료제로 사용되고 있다. 본 연구에서는 저온에서 전처리한 B . japonicum 균주를 여러 가지 환경스트레스 조건에 노출하였을 때 생균수의 변화를 확인하였다. 저온 전처리는 16시간 동안 $4^{\circ}C$의 조건을 유지했다. 다양한 스트레스(알콜, 과산화수소, 고온, 건조)에 노출하였을 때, 저온 전처리한 것이 그렇지 않는 것보다 10~1,000배 정도 높은 생균수를 유지하였다. 이러한 내성중진 현상에 전처리 동안 새로운 단백질 합성이 수반되는 것을 단백질 합성 저해제 인 chloramphenicol을 전처리 과정에 포함하여 확인하였다. 저온 스트레스 내성에 관여하는 유전자를 B. japonicum genome 으로부터 중폭하였고 염기서열 분석을 실시하였다. 실험에서 확인된 B . japonicum의 CSP (Cold shock protein) 단백질의 부분적 아미노산 서열은 이미 확인된 다른 균주의 Csp 단백질과 유사함을 확인하였다.

• 한국식생활문화학회지
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• 제29권2호
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• pp.212-221
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• 2014

Korean style DASH (Dietary Approaches to Stop Hypertension) and a dietary education program for sodium reduction were developed. Reduced sodium diets (15 and 30% reductions) were developed from general diets for 3 consecutive weeks from Monday through Saturday. Subjects (19 total) were classified into two groups according to dietary education. Experimental period was from June 24 to July 23, 2012. Total sum of adaptation scores for low sodium diets significantly increased in the group that underwent dietary education compared to that without (p<0.05). After the experiment, both groups showed significantly increased values in terms of food group balance, sodium-related nutrition knowledge, attitude, and practice by paired t-test. Especially, group that underwent dietary education showed significantly higher values for attitudes by ANCOVA pre-test as a variation (p<0.01). For the results of the nutrient intake survey, group that underwent dietary education showed significantly increased values for dietary fiber (p<0.01), vitamin A (p<0.001), vitamin K (p<0.001), vitamin C (p<0.01), Folic acid (p<0.001), vitamin B12 (p<0.01), calcium (p<0.01), iron (p<0.05), and zinc (p<0.05) and significantly decreased values for sodium (p<0.05) and chloride (p<0.005). Subjects adapted to reduced sodium diets showed apparent improvements in sodium-related knowledge, attitude, practice and intake of nutrient, and these improvements were even higher in the group that underwent dietary education compared to that without. Thus, adaptation to low sodium diet combined with dietary education can improve dietary habits.

• Genes and Genomics
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• 제40권11호
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• pp.1169-1180
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• 2018

Cave shrimps from the genera Typhlatya, Stygiocaris and Typhlopatsa (TST complex) comprises twenty cave-adapted taxa, which mainly occur in the anchialine environment. Anchialine habitats may undergo drastic environmental fluctuations, including spatial and temporal changes in salinity, temperature, and dissolved oxygen content. Previous studies of crustaceans from anchialine caves suggest that they have possessed morphological, behavioral, and physiological adaptations to cope with the extreme conditions, similar to other cave-dwelling crustaceans. However, the genetic basis has not been thoroughly explored in crustaceans from anchialine habitats, which can experience hypoxic regimes. To test whether the TST shrimp-complex hypoxia adaptations matched adaptive evolution of mitochondrial OXPHOS genes. The 13 OXPHOS genes from mitochondrial genomes of 98 shrimps and 1 outgroup were examined. For each of these genes was investigated and compared to orthologous sequences using both gene (i.e. branch-site and Datamonkey) and protein (i.e. TreeSAAP) level approaches. Positive selection was detected in 11 of the 13 candidate genes, and the radical amino acid changes sites scattered throughout the entire TST complex phylogeny. Additionally, a series of parallel/convergent amino acid substitutions were identified in mitochondrial OXPHOS genes of TST complex shrimps, which reflect functional convergence or similar genetic mechanisms of cave adaptation. The extensive occurrence of positive selection is suggestive of their essential role in adaptation to hypoxic anchialine environment, and further implying that TST complex shrimps might have acquired a finely capacity for energy metabolism. These results provided some new insights into the genetic basis of anchialine hypoxia adaptation.

• 한국육종학회지
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• 제41권4호
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• pp.664-668
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• 2009

"보람"은 조숙, 다수성이며 바이오디젤 생산 및 식용으로 이용이 가능한 유채 로 2006년에 목포-CGMS(웅성불임)과 8634-B-1-3-1-8(임성회복화분친)을 교배하여 2007년부터 2008년까지 생산력 검정시험과, 2008년 지역적응시험을 거쳐 육성된 품종이다. "보람"의 엽형은 하부익상전렬, 엽색 및 줄기색은 녹색, 결각은 중간이며 꽃색은 황색, 종피색은 흑색이다. 개화기(4월 9일)와 성숙기(6월 4일)는 "선망"과 비슷하나 "탐미유채"보다는 개화는 6일, 성숙기는 3일 정도 빠르다. 지역적응 시험시험 결과, "보람"의 수량은 10a 당 424 kg로 같은 1대 잡종인 "선망"에 비해 11%, 고정종인 "탐미유채"에 비해 48% 증수되었다. "보람"의 기름함량은 44.2%이고, 올레인산의 함량은 68.5%로 "탐미유채"와 "선망"에 비해 각각 3.7%와 5.4%높아져 바이오디젤 생산용으로 적합하며, 구루코지노레이트 함량은 2.27 mg/g으로 국제허용기준치인 3.0 mg/g 이하였다. "보람"은 전남, 전북, 경남 및 제주도를 포함하는 우리나라의 서남부지역에서 재배에 적합한 품종이다.