Papers by Watanalai Panbangred
Research Journal of Microbiology, Jun 1, 2011
Genome Announcements, Oct 27, 2016
We report here the draft genome sequence of Streptomyces sp. SPMA113 isolated from soil in Thaila... more We report here the draft genome sequence of Streptomyces sp. SPMA113 isolated from soil in Thailand. This strain produces a new modified peptide, prajinamide, which has adipocyte differentiation activity. The genome harbors at least 30 gene clusters for synthases of polyketide and nonribosomal peptide, suggesting its potential to produce diverse secondary metabolites.
PubMed, Sep 1, 1990
Human salmonellosis due to Salmonella krefeld is very rare. During 1976-1978, a large outbreak of... more Human salmonellosis due to Salmonella krefeld is very rare. During 1976-1978, a large outbreak of S. krefeld gastroenteritis occurred in Thailand, mainly in children. The majority of strains were multiply drug resistant with high minimum inhibitory concentration (MIC). The MIC for these drugs were ampicillin (Ap) 256-4096 mg/l, chloramphenicol (Cm) 256-512 mg/l, kanamycin (Km) 512- greater than 4096 mg/l, streptomycin (Sm) greater than 1024 mg/l, sulfamethoxazole (Su) 4096- greater than 8192 mg/l, tetracycline (Tc) 64-128 mg/l and trimethoprim (Tp) 64-256 mg/l. Resistance to Su and Tp declined after the period of the epidemic. The resistance genes were found to be highly transferable at a rate of 10(-2) to 10(-4). All strains with more than five resistance markers had large molecular weight plasmids of 120-140 megadaltons. The restriction profile analysis of plasmids from isolates collected from various regions of the country showed similarity of DNA fragment pattern. These isolates were resistant to Ap, Cm, Km, Sm, Su and Tc.
Food Biotechnology, May 4, 2009
We developed a one-step method based on multiplex-overlapping polymerase chain reaction (mPCR) fo... more We developed a one-step method based on multiplex-overlapping polymerase chain reaction (mPCR) for species differentiation of Pediococcus acidilactici and P. pentosaceus as well as simultaneous detection of pediocin (ped) gene. The mPCR was performed in a single reaction tube with six primers consisting of four primers for identification of P. acidilactici and P. pentosaceus and two primers for pediocin gene
PubMed, Jun 1, 1990
Sulfonamide (Su) and trimethoprim (Tp) resistance are known to caused by the production of drug r... more Sulfonamide (Su) and trimethoprim (Tp) resistance are known to caused by the production of drug resistant dihydropteroate synthase (DHPS) and dihydrofolate reductase (DHFR), respectively. Sulfonamide and trimethoprim are often used in combination under the name cotrimoxazole. Cotrimoxazole resistance in various enteric bacteria isolated at Ramathibodi Hospital was studied. The rate of resistance from 1984-1989 of many genera was rather constant at 40%-60% except in Shigella spp in which the rate increased rapidly in 1987 till 1989. Seventy-five percent of Su-Tp resistant (Sur-Tpr) bacteria were also found to be resistant to other drugs such as ampicillin, aminoglycosides, tetracycline and chloramphenicol in addition to cotrimoxazole. Two hundred and forty Su-Tp resistant strains were analysed for the presence of type I and II dihydropteroate synthase as well as type I and V dihydrofolate reductase genes by hybridization with the corresponding gene probes. Type I DHPS gene predominated in Su-Tp resistant bacteria at 60.8% whereas type II DHPS was found in only 25%. Some strains (11.7%) had both genotypes but 2.5% did not have any. In the trimethoprim resistance study, the DHFR type I gene was also found more frequently (30%) whereas type V DHFR was only 19%. The remaining of Tp resistance (51%) was unclassified. The coexistence of Su and Tp resistance genes of each type was investigated among 118 Su and Tp resistant strains. It was found that type I DHPS gene was found together with either type I or V DHFR gene and type II DHPS was found with type I DHFR gene at about the same rate (28.9%, 27.1% and 26.3%, respectively). However, the presence of type II DHPS together with type V DHFR was rather low, only 5.9% of isolates were found to have both types of genes.
The Journal of Antibiotics, Sep 3, 2019
A norditerpenoid k4610422 (1), an inhibitor of testosterone-5α-reductase originally discovered fr... more A norditerpenoid k4610422 (1), an inhibitor of testosterone-5α-reductase originally discovered from a mesophilic rare actinomycete of the genus Streptosporangium, was isolated from the culture extract of a thermophilic actinomycete Actinomadura sp. The complete 1H and 13C NMR assignment and absolute configuration of 1 were addressed by spectroscopic measurements including NOESY and CD spectra coupled with ECD calculation, which allowed to establish the (5 R,9 S,10 R,13 S)-configuration. Compound 1 was moderately cytotoxic against P388 murine leukemia cells with IC50 30 μM.
The Journal of Antibiotics, Feb 8, 2017
Castration-resistant prostate cancer (CRPC) is the most aggressive form of this disease. CRPC rem... more Castration-resistant prostate cancer (CRPC) is the most aggressive form of this disease. CRPC remains dependent on androgen receptor (AR) signaling. Therefore, a novel AR antagonist, enzalutamide, is used clinically for the treatment of men with metastatic CRPC. However, enzalutamide-resistant AR has appeared, and a new type of AR antagonist is desired. Previously, in the course of screening for a new type of AR antagonist, we isolated a series of compounds, designated antarlides A-E, that share a novel 22-membered-ring macrocyclic structure and are produced by Streptomyces sp. BB47. In the present study, we found that this strain also produces antarlides F-H as minor components. Antarlide F is a novel geometric isomer of known antarlides. On the other hand, antarlides G and H are new members of the antarlide family that have a 20-membered-ring macrocyclic structure. Antarlides G and H inhibited the binding of androgen to AR in vitro at concentrations similar to those observed with antarlides A-E. In addition, antarlide G inhibited the transcriptional activity of not only wild-type AR but also enzalutamide-resistant AR, suggesting that antarlides with either 22-or 20-membered rings may serve as potent third-generation AR antagonists capable of overcoming resistance to enzalutamide.
Journal of Bioscience and Bioengineering, Apr 1, 2011
Propionibacterium acidipropionici TISTR442 produced the highest amount of 5-aminolevulinic acid (... more Propionibacterium acidipropionici TISTR442 produced the highest amount of 5-aminolevulinic acid (ALA) when cultivated in medium supplemented with glycine at 18 g/l. ALA production correlated with ALA synthase activity, whereas ALA dehydratase activity was maintained at a low level. ALA yield reached 405 mg/l after prolonged cultivation for 1 month.
A phytase produced by the soil bacterium Klebsiella pneumoniae subsp. pneumoniae strain XY-5 was ... more A phytase produced by the soil bacterium Klebsiella pneumoniae subsp. pneumoniae strain XY-5 was isolated and purified. The enzyme was a single chain protein with a molecular mass of 41.7 kDa, as determined by SDS-PAGE. The isoelectric point (pI) of the native enzyme was found to be 8.7. It exhibited two pH optima (3.7 and 5.5) when assayed both at 37°C (297 units/ mg protein) and 55°C (318 units/ mg protein) and it was found to be stable up to 60°C for 4.0 hours. The enzyme was found to have broad substrate specificity. It was activated by EDTA, Al 3+ and Co 2+ , but was strongly inhibited by Hg 2+. The putative gene encoding the phytase was cloned by PCR, and DNA sequencing revealed an ORF of 1269 nucleotides downstream from a potential ribosome-binding site. The deduced amino acid sequence of the mature protein comprised 394 aa with a calculated molecular mass of 43.4 kDa and a signal peptide consisting of 28 aa. The mature enzyme contained the conserved active site RHGXRXP and an HD motif that placed it in the histidine acid phosphatase (HAPs) family. Expression of the cloned gene in an E. coli yielded active phytase. Due to its relatively high specific activity, broad substrate specificity, good pH profile and temperature stability, the enzyme could be a good candidate for industrial applications.
BioMed Research International, 2015
The Salmonella enterotoxin (stn) gene exhibits high homology among S. enterica serovars and S. bo... more The Salmonella enterotoxin (stn) gene exhibits high homology among S. enterica serovars and S. bongori. A set of 6 specific primers targeting the stn gene were designed for detection of Salmonella spp. using the loop-mediated isothermal amplification (LAMP) method. The primers amplified target sequences in all 102 strains of 87 serovars of Salmonella tested and no products were detected in 57 non-Salmonella strains. The detection limit in pure cultures was 5 fg DNA/reaction when amplified at 65 ∘ C for 25 min. The LAMP assay could detect Salmonella in artificially contaminated food samples as low as 220 cells/g of food without a preenrichment step. However, the sensitivity was increased 100-fold (∼2 cells/g) following 5 hr preenrichment at 35 ∘ C. The LAMP technique, with a preenrichment step for 5 and 16 hr, was shown to give 100% specificity with food samples compared to the reference culture method in which 67 out of 90 food samples gave positive results. Different food matrixes did not interfere with LAMP detection which employed a simple boiling method for DNA template preparation. The results indicate that the LAMP method, targeting the stn gene, has great potential for detection of Salmonella in food samples with both high specificity and high sensitivity.
Applied Microbiology and Biotechnology, Aug 1, 1985
A hybrid plasmid, pOXN29 (10.4 Mdal), coding the xylanase (xynA) and ß-xylosidase (xynB) genes of... more A hybrid plasmid, pOXN29 (10.4 Mdal), coding the xylanase (xynA) and ß-xylosidase (xynB) genes of Bacillus pumilus IPO was constructed by the ligation of pBR322 and a 7.7 Mdal PstI-fragment of chromosomal DNA as reported in our previous paper (Panbangred et al. 1983). A deletion plasmid of pOXN29, pOXN293 (9.2 Mdal), which contains xynA and xynB, was ligated with pUB110 at an EcoRI site, and used to transform B. subtilis MI111. Two selected clones of B. subtilis as xylanase hyper-producers contained plasmids pOXW11 (4.2 Mdal) and pOXW12 (4.0 Mdal), both consisting of only pUB110, xynA, and its flanking regions, as the result of spontaneous deletion. These B. subtilis clones produced 2.7–3.0 times as much xylanase as B. pumilus.
FEBS Letters, Jun 11, 1984
The complete nucleotide sequence of the xylanase (EC 3.2.1.8) gene (xywl) and its flanking region... more The complete nucleotide sequence of the xylanase (EC 3.2.1.8) gene (xywl) and its flanking regions of Bacillus pumilus IPO, a hyperproducer of xylanase, was determined. A 684 bp open reading frame for xylanase gene was observed. The amino acid sequence of the N-terminal region of xylanase was determined to be Arg-Thr-Be-Thr-, suggesting the processing at Ala" of pre-xylanase. The amino acid composition and i%4, (22384) of xylanase deduced from DNA sequence agreed with the results obtained with the purified enzyme. The signal sequence consisted of 27 amino acids, of which 3 were basic amino acid residues in the region near the N-terminus and 15 were hydrophobic amino acid residues. The ribosome binding sequence complementary to the 3'-end of 16 S rRNA of B. subtilis was found7 bp upstream of the initiation codon, ATG. Bacillus pumilus Xylanase DNA sequence Signal sequence Gene cloning Ribosome binding sequence
Tubercle and Lung Disease, Jun 1, 1993
Strain characterization of Mycobacterium tuberculosis has been based mainly on mycobacteriophage ... more Strain characterization of Mycobacterium tuberculosis has been based mainly on mycobacteriophage typing or chromosomal DNA restriction fragment analysis. In this study 10 randomly selected EcoRI chromosomal DNA fragments of M. tuberculosis H37RV were labelled with digoxigenin and used to probe the Southern blot preparation of EcoRI or BstEII digested chromosomal DNA of clinical isolates of M. tuberculosis. 2 probes were able to reveal restriction fragment length polymorphism. Each of the probes divided 15 pulmonary and 6 cerebrospinal fluid (CSF) isolates of M. tuberculosis into 3 groups and combination of both probes divided them into 4 groups. All of the 6 CSF isolates belonged to 1 group while only 5 of the 15 pulmonary isolates belonged to the same group. Work is continuing in order to characterize the nature of the probe and confirm the results in a larger population.
Journal of the Science of Food and Agriculture, Jan 10, 2017
BACKGROUNDMixed larvae and pupae of weaver ant (Oecophylla smaragdina) are widely used as an impo... more BACKGROUNDMixed larvae and pupae of weaver ant (Oecophylla smaragdina) are widely used as an important food ingredient in regions of Thailand. They have high nutritional values and comprise 53% protein and 13% lipid. Peptides derived from food proteins have been shown to possess biological activities.RESULTSPeptides derived from pepsin and trypsin digestion of these weaver ant larvae and pupae were purified based on angiotensin‐converting enzyme (ACE) inhibitory and antioxidant activities, and their amino acid sequences were identified by liquid chromatography–tandem mass spectrometry (LC‐MS/MS). In silico docking of peptides with ACE successfully predicted the inhibitory peptides as confirmed by their chemical synthesis. Two peptides with sequences of FFGT and LSRVP showed IC50 values for ACE inhibition of 19.5 ± 1.7 and 52.7 ± 4.0 µmol L−1, respectively. In addition, one potent antioxidant peptide with a sequence of CTKKHKPNC showed IC50 values of 48.2 ± 2.1 µmol L−1 for DPPH assay and 38.4 ± 0.2 µmol L−1 for ABTS assay, respectively.CONCLUSIONThese results indicate that proteins from larvae and pupae of weaver ants are potential sources of peptides with anti‐ACE and antioxidation bioactivities. © 2016 Society of Chemical Industry
Applied and Environmental Microbiology, Mar 15, 2012
Seven distinct Bacillus thuringiensis subsp. aizawai integrants were constructed that carried the... more Seven distinct Bacillus thuringiensis subsp. aizawai integrants were constructed that carried the chitinase (chiBlA) gene from B. licheniformis under the control of the cry11Aa promoter and terminator with and without p19 and p20 genes. The toxicity of B. thuringiensis subsp. aizawai integrants against second-instar Spodoptera litura larvae was increased 1.8-to 4.6-fold compared to that of the wild-type strain (BTA1). Surprisingly, the enhanced toxicity in some strains of B. thuringiensis subsp. aizawai integrants (BtaP19CS, BtaP19CSter, and BtaCAT) correlated with an increase in toxin formation. To investigate the role of these genes in toxin production, the expression profiles of the toxin genes, cry1Aa and chiBlA, as well as their transcriptional regulators (sigK and sigE), were analyzed by quantitative real-time RT-PCR (qPCR) from BTA1, BtaP19CS, and BtaCAT. Expression levels of cry1Aa in these two integrants increased about 2-to 3-fold compared to those of BTA1. The expression of the transcription factor sigK also was prolonged in the integrants compared to that of the wild type; however, sigE expression was unchanged. Western blot analysis of E and K showed the prolonged accumulation of E in the integrants compared to that of BTA1, resulting in the increased synthesis of pro-K up to T 17 after the onset of sporulation in both BtaP19CS and BtaCAT compared to that of T 13 in BTA1. The results from qPCR indicate clearly that the cry1Aa promoter activity was influenced most strongly by E , whereas cry11Aa depended mostly on K. These results on large-crystal toxin formation with enhanced toxicity should provide useful information for the generation of strains with improved insecticidal activity.
Research Journal of Biotechnology, Mar 25, 2022
A bacterium strain with nebular growth pattern was isolated from a rice field and was identified ... more A bacterium strain with nebular growth pattern was isolated from a rice field and was identified as Paenibacillus alvei WW001. The isolate exhibited several plant-growth promoting activities including solubilization of tri-calcium phosphate at 1,152.9 μg/ml after 6 days of cultivation and production of indole acetic acid (IAA) which reached the maximum concentration of 5.1 μg/ml after 4 days of cultivation in nitrogen free medium supplemented with L-tryptophan. In addition, high production of ammonia and siderophore was detected on day 7 of cultivation (1.7 μmol/ml and 60% siderophore units respectively). Gibberellic acid production from a dayold culture in LB broth was quantified to be 79.6 μg/ml. Strain WW001 also displayed an ACC deaminase activity, albeit at a low level. Its cell-free culture supernatant (CFCS) showed antimicrobial activity against bacterial phytopathogen; Pectobacterium carotovorum DoA 263, Xanthomonas campestris DoA 1869 and X. axonopodis at 40, 1280 and 1280 Arbitrary Unit (AU)/ml respectively. Tricine SDSPAGE analysis revealed a 3-kDa peptide associated with the observed inhibitory effect. Treating mung bean seedlings (n=30) with strain WW001 only or mixture of strain WW001 and X. campestris resulted in longer roots and higher total dry weights. Collectively, both in vitro and in vivo results attested that P. alvei WW001 is an efficient plant growth promoting rhizobacterium (PGPR) with a potent activity against bacterial phytopathogen.
Scientific Reports, Jun 3, 2021
In vivo selection systems are powerful tools for directed evolution of enzymes. The selection pre... more In vivo selection systems are powerful tools for directed evolution of enzymes. The selection pressure of the systems can be tuned by regulating the expression levels of the catalysts. In this work, we engineered a selection system for laboratory evolution of highly active enzymes by incorporating a translationally suppressing cis repressor as well as an inducible promoter to impart stringent and tunable selection pressure. We demonstrated the utility of our selection system by performing directed evolution experiments using TEM β-lactamase as the model enzyme. Five evolutionary rounds afforded a highly active variant exhibiting 440-fold improvement in catalytic efficiency. We also showed that, without the cis repressor, the selection system cannot provide sufficient selection pressure required for evolving highly efficient TEM β-lactamase. The selection system should be applicable for the exploration of catalytic perfection of a wide range of enzymes.
International Journal of Food Science and Technology, Nov 7, 2020
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Papers by Watanalai Panbangred