• Mycobiology
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• v.46 no.4
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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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• v.27 no.8
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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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• v.20 no.3
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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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• v.21 no.3
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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.

• Biomedical Science Letters
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• v.6 no.4
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• pp.229-235
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• 2000

In situ brain-pancreas perfusion was performed on male adult Sprague-Dawley rats, of which the central nervous systems (CNS) were intact during the perfusion procedure. The modified Krebs-Ringer buffer with 100 mg/dL of glucose and 20 mM of arginine was perfused for 30 min. In the experimental groups, a cephalic glucopenia was induced at 0 min (GLP1 group) or at 16 min (GLP2 group). The glucopenia was not induced in the control (CONT group). Insulin and glucagon concentrations in the effluent samples from the pancreas were measured using a RIA method. In all three groups, the first and second phases in the dynamics of the insulin and glucagon secretion were observed, which was a typical biphasic secretory pattern. The amount of insulin secretion tended to decrease in the GLP1 and GLP2 groups, but there was no statistically significant difference among the groups. However, the amount of glucagon secretion during 0~15 min of the perfusion period in the GLP1 group was greater as compared to the CONT group (p<0.05). The amount of glucagon secretion during 16~30 min of the perfusion period in the GLP2 group tended to be greater as compared to the CONT group, however there was no statistical significance. These data indicate that the cephalic glucopenia stimulates the direct secretion of glucagon from the pancreas during the early period of perfusion in the CNS-intact pancreatic perfused rats.