• Mycobiology
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• 제46권4호
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• pp.407-415
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• 2018

Pheromone (PHB)-receptor (RCB) interaction in the mating pheromone response pathway of Lentinula edodes was investigated using synthetic PHBs. Functionality of the C-terminally carboxymethylated synthetic PHBs was demonstrated by concentration-dependent induction of a mating-related gene (znf2) expression and by pseudoclamp formation in a monokaryotic strain S1-11 of L. edodes. Treatment with synthetic PHBs activated the expression of homeodomain genes (HDs) residing in the A mating type locus, and of A-regulated genes, including znf2, clp1, and priA, as well as genes in the B mating type locus, including pheromone (phb) and receptor (rcb) genes. The synthetic PHBs failed to discriminate self from non-self RCBs. PHBs of the B4 mating type (B4 PHBs) were able to activate the mating pheromone response pathway in both monokaryotic S1-11 and S1-13 strains, whose B mating types were B4 (self) and B12 (non-self), respectively. The same was true for B12 PHBs in the B4 (non-self) and B12 (self) mating types. The synthetic PHBs also promoted the mating of two monokaryotic strains carrying B4-common incompatible mating types ($A5B4{\times}A1B4$). However, the dikaryon generated by this process exhibited abnormally high content of hyphal branching and frequent clamp connections and, more importantly, was found to be genetically unstable due to overexpression of mating-related genes such as clp1. Although synthetic PHBs were unable to discriminate self from non-self RCBs, they showed a higher affinity for non-self RCBs, through which the mating pheromone response pathway in non-self cells may be preferentially activated.

• Bulletin of the Korean Chemical Society
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• 제27권8호
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• pp.1149-1153
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• 2006

LPC analogues including natural and unnatural LPC, 3-L-2-PC, acetylated LPC and ethylene glycol derivative are prepared from D-mannitol using in convenient procedures by only changing the synthetic sequences, and their protective activities against cecal ligation and puncture (CLP)-induced severe sepsis are compared. The chirality at C2 position in LPC is found to be required as (S)-configuration for sepsis inhibition, comparing from the protection activity between LPC 6 and unnatural LPC 8. The hydroxyl functionality is also very important and required at C2 or C3 position as shown in the protection activities of ethylene glycol analogue 11 and 3-L-2-PC 9.

• Journal of Ginseng Research
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• 제20권3호
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• pp.325-330
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• 1996

Dynamic parameters of physiology including embryo ratio (ER), embryo length to endosperm length, dry weight ratio between embryo and endosperm (DWR) and respiration rate (RR) in American send (Panax quinquefolium L.) seed were investigated. According to the changes of ER during seed stratification, the duration of embryo afterripening could be divided into three stages as \circled1 embryo slow growth stage (ESGS), ER increased from 7.31% to 20.48% (0.16% day-1): \circled2 embryo rapid growth stage (ERGS), ER increased to 80.98% (0.61% day-1) (75G5+ ERGS=morphological afterripening stage (MP,5)) and \circled3pysiological afterripening stage (PAS), ER Increased to 88.50% (0.094 day-1) only. DWR Increased slowly from 0.20% to 2.76clp (0.016% day-1) in MAS and rapidly to 8.81% (0.061% day-1) in PAS. The RR correlated significantly with ER as well (r=0.8934 > rot, 0.6610). The steep increment of both DWR and RR in PAS indicated that the PAS was not a static stage although the ER was not changed too much. All of these may provide some information for understanding the dormancy mechanisms of American sting seed.

• Genomics & Informatics
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• 제21권3호
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• pp.35.1-35.12
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• 2023

The Bacillus cereus group, also known as B. cereus sensu lato (B. cereus s.l.), is composed of various Bacillus species, some of which can cause diarrheal or emetic food poisoning. Several emerging highly heat-resistant Bacillus species have been identified, these include B. thermoamylovorans, B. sporothermodurans, and B. cytotoxicus NVH 391-98. Herein, we performed whole genome analysis of two thermotolerant Bacillus sp. isolates, Bacillus sp. B48 and Bacillus sp. B140, from an omelet with acacia leaves and fried rice, respectively. Phylogenomic analysis suggested that Bacillus sp. B48 and Bacillus sp. B140 are closely related to B. cereus and B. thuringiensis, respectively. Whole genome alignment of Bacillus sp. B48, Bacillus sp. B140, mesophilic strain B. cereus ATCC14579, and thermophilic strain B. cytotoxicus NVH 391-98 using the Mauve program revealed the presence of numerous homologous regions including genes responsible for heat shock in the dnaK gene cluster. However, the presence of a DUF4253 domain-containing protein was observed only in the genome of B. cereus ATCC14579 while the intracellular protease PfpI family was present only in the chromosome of B. cytotoxicus NVH 391-98. In addition, prophage Clp protease-like proteins were found in the genomes of both Bacillus sp. B48 and Bacillus sp. B140 but not in the genome of B. cereus ATCC14579. The genomic profiles of Bacillus sp. isolates were identified by using whole genome analysis especially those relating to heat-responsive gene clusters. The findings presented in this study lay the foundations for subsequent studies to reveal further insights into the molecular mechanisms of Bacillus species in terms of heat resistance mechanisms.

• 대한의생명과학회지
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• 제6권4호
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• pp.229-235
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• 2000

췌장에서 분비하는 인슐린과 글루카곤의 자극-분비 coupling 과정은 주로 혈당 농도와 중추신경계에 의하여 조절되어진다. 본 연구는 두부에 포도당이 결핍되었을 때에 중추신경계가 췌장에서 인슐린과 글루카곤이 분비되는 패턴을 Sprague-Dawley 흰쥐를 대상으로 하여 살펴보았으며, 실험 방법은 in situ 뇌-췌장 관류법을 이용하였다. 관류액은 100 mg/dL glucose와 20 mM arginine를 포함한 Krebs-Ringer 완충액 (pH 7.4)으로 하였으며, 95% $O_2$-5% $CO_2$ 가스를 계속적으로 주입시키면서 5 ml/min의 속도로 30분간 정주하였다. 대조군은 cephalic glucopenia가 일어나지 않는 군으로 하였고, 실험군은 두 군으로 나누어서 GLP1군은 cephalic glucopenia가 0분에 일어나도록 하였고, CLP2군은 16분에 일어나도록 하였다. 문맥으로 유출되는 췌장의 effluent액에서 인슐린과 글루카곤 농도를 RIA법으로 측정하였고 호르몬의 분비 속도를 산출하여 분비동태 양상을 분석하였다. 결과에서 인슐린 분비량은 GLP1군에서 가장 낮아서 cephalic glucopenia에 의하여 다소 감소하는 경향이었으나, 세 군간에 통계적으로 유의적인 차이는 없었다. 인슐린의 분비동태 양상을 살펴보면 이봉성의 정규 양상을 보였으나, GLP1군에서 첫번째 peak (4 min)가 다소 둔화되는 현상을 보였다. 글루카곤의 분비동태 양상도 이봉성의 정규 양상을 보였으며, 특히 GLP1군에 있어서 0~15분간의 글루카곤 분비량은 cephalic glucopenia에 의하여 유의성 있게 (p<0.05) 증가하였다. GLP2군에 있어서 글루카곤 분비량은 관류 후 15~30분 사이에 중가하는 경향을 볼 수 있었으나 통계적인 유의성은 없었다. 따라서 頭部의 포도당 결핍은 글루카곤의 분비를 증가시키는 것으로 나타났고, 이러한 현상은 특히 관류의 early period에서 현저하였다.