scholarly journals Polymorphism at four-fold degenerate site, but not at the intergenic regions, explains nucleotide compositional strand asymmetry in bacteria

2021 ◽  
Author(s):  
Piyali Sen ◽  
Ruksana Aziz ◽  
Soumita Das ◽  
Nima Dondu Namsa ◽  
Ramesh Chandra Deka ◽  
...  

We investigated single nucleotide polymorphism in intergenic regions (IRs) and four-fold degenerate sites (FFS) in genomes of three γ-Proteobacteria and two Firmicutes to understand the mechanism of nucleotide compositional asymmetry between the leading and the lagging strands. Pattern of the polymorphism spectra were alike regarding transitions but variable regarding transversions in the IRs of these bacteria. Contrasting trends of complementary polymorphisms such as C->T vs G->A as well as A->G vs T->C in the IRs vindicated similar replication-associated strand asymmetry regarding cytosine and adenine deamination, respectively, across these bacteria. Surprisingly, the polymorphism pattern at FFS was different from that of the IRs and its frequency was always more than the IRs in these bacteria. Further, the polymorphism patterns within a bacterium were inconsistent across the five amino acids, which neither the replication nor the transcription-associated mutations could explain. However, the polymorphism at FFS coincided with amino acid specific codon usage bias in the five bacteria. Further, strand asymmetry in nucleotide composition could be explained by the polymorphism at FFS, not at the IRs. Therefore, polymorphisms at FFS might not be treated as nearly neutral unlike that in IRs in these bacteria.

2018 ◽  
Vol 43 (4) ◽  
pp. 309
Author(s):  
N. Hilmia ◽  
D. Rahmat ◽  
D. Dudi

Point mutation on exon 2 of leptin gene, which changes amino acid encoding from Arginine to Cysteine, may alters the physiological function of the leptin hormone. This study aimed to identify leptin gene polymorphism of Ongole Grade (OG) cattle based on Single Nucleotide Polymorphism (SNP). The DNA sample was taken from 48 head of OG cattle at Balai Pengembangan Perbibitan Ternak Sapi Potong(BPPT SP) Cijeungjing West Java, which was isolated from white blood cell using the high salt method. Amplification of DNA was done by Polymerase Chain Reaction (PCR), followed by direct sequencing to obtain nucleotide sequence. The SNP analysis was carried out from alignment of sequencing result using Bioedit and MEGA 5.2 program. The results indicated in exon 2 leptin gene of OG cattle there was one synonymous SNPs that did not changeamino acids Serine encoding on g.1025T >C/S17S, while two non synonymous SNPaltered amino acids encoding, those were g.1047C> T /R25C and g.1048G>A/R25H. Those mutations changed amino acids encoding from Arginine to Cysteine and Arginine to Histidine respectively.In OG cattle, the frequency of A allele (44.8%) was higher than C allele (33.3%) and T allele (21.9%). Six genotypes were also identified, i.e. AA (41.7%), CC (20.8%), CT (20.8%), CA(4.2%), TT (10.4%) and TA (2.1 %). Heterozigosity of OG cattle based on leptin gene was 0.65 that was a high category. The A allele was a specific allele on Indonesian local cattle.


2006 ◽  
Vol 74 (12) ◽  
pp. 7014-7020 ◽  
Author(s):  
Shuichi Nishikubo ◽  
Masaru Ohara ◽  
Masae Ikura ◽  
Katsuo Katayanagi ◽  
Tamaki Fujiwara ◽  
...  

ABSTRACT Clinical Actinobacillus actinomycetemcomitans produces cytolethal distending toxin (CDT) with titers ranging from 102 to 108 U/mg. Single nucleotide polymorphism analysis of the cdt gene in clinical isolates identified a variation of a single amino acid at residue 281 of CdtB, which significantly affected CDT toxicity by modulating the chromatin-degrading activity of CdtB.


2021 ◽  
Vol 57 (4) ◽  
pp. 159-168
Author(s):  
Huỳnh Kỳ ◽  
Đặng Thành Phát Trần ◽  
Thị Kim Phụng Nguyễn ◽  
Văn Quốc Giang ◽  
Văn Mạnh Nguyễn ◽  
...  

Trong nghiên cứu này, kỹ thuật giải trình tự thế hệ mới (next generation sequencing) được ứng dụng để giải trình tự của bộ gene 2 giống lúa Đốc Phụng (giống chống chịu mặn) và giống Nếp Mỡ (giống mẫn cảm với mặn), nhằm tìm các chỉ thị phân tử là gene chức năng mà các gene này liên quan đến cơ chế chống chịu mặn có trong giống lúa Đốc Phụng. Kết quả so sánh với bộ gene tham chiếu, bộ gene của giống lúa Đốc Phụng có khoảng 1.918.726 biến thể dạng thay đổi một nucleotide (Single Nucleotide Polymorphism) và và chèn vào khoảng 81.435, mất đi khoảng 81.974. Trong khi đó ở giống Nếp Mỡ, có khoảng 1.931.380 SNP và chèn vào khoảng 88.473, mất đi khoảng 83.190 vùng DNA. Đa số các biến thể xuất hiện ở các vùng không mang chức năng như trước sau và giữa các gene chiếm tỉ lệ trên 75%. Kết quả khảo sát biến thể xuất hiện trong vùng gene OsTZF1 (LOC_Os05g10670.1), có chức năng điều hòa các nhóm gene liên quan đến các yếu tố stress sinh học và phi sinh học, cho thấy ở giống Đốc Phụng có 7 biến thể SNP và có chèn thêm 9 nucleotide mã hóa 3 amino acid arginine khi so với giống Nếp Mỡ dựa trên bộ gene tham chiếu. Thông tin này giúp cho các nhà chọn giống sử dụng nó như chi thị phân tử, chọn tạo giống chống chịu...


2008 ◽  
Vol 53 (3) ◽  
pp. 977-986 ◽  
Author(s):  
C. Hal Jones ◽  
Alexey Ruzin ◽  
Margareta Tuckman ◽  
Melissa A. Visalli ◽  
Peter J. Petersen ◽  
...  

ABSTRACT TEM- and SHV-type extended-spectrum β-lactamases (ESBLs) are the most common ESBLs found in the United States and are prevalent throughout the world. Amino acid substitutions at a number of positions in TEM-1 lead to the ESBL phenotype, although substitutions at residues 104 (E to K), 164 (R to S or H), 238 (G to S), and 240 (E to K) appear to be particularly important in modifying the spectrum of activity of the enzyme. The SHV-1-derived ESBLs are a less diverse collection of enzymes; however, the majority of amino acid substitutions resulting in an ESBL mirror those seen in the TEM-1-derived enzymes. Pyrosequencing by use of the single-nucleotide polymorphism (SNP) protocol was applied to provide sequence data at positions critical for the ESBL phenotype spanning the bla TEM and bla SHV genes. Three novel β-lactamases are described: the ESBLs TEM-155 (Q39K, R164S, E240K) and SHV-105 (I8F, R43S, G156D, G238S, E240K) and a non-ESBL, SHV-48 (V119I). The ceftazidime, ceftriaxone, and aztreonam MICs for an Escherichia coli isolate expressing bla SHV-105 were >128, 128, and >128 μg/ml, respectively. Likewise, the ceftazidime, ceftriaxone, and aztreonam MICs for an E. coli isolate expressing bla TEM-155 were >128, 64, and > 128 μg/ml, respectively. Pyrosequence analysis determined the true identity of the β-lactamase on plasmid R1010 to be SHV-11 rather than SHV-1, as previously reported. Pyrosequencing is a real-time sequencing-by-synthesis approach that was applied to SNP detection for TEM- and SHV-type ESBL identification and represents a robust tool for rapid sequence determination that may have a place in the clinical setting.


Blood ◽  
2007 ◽  
Vol 109 (12) ◽  
pp. 5286-5292 ◽  
Author(s):  
Victoria J. Christiansen ◽  
Kenneth W. Jackson ◽  
Kyung N. Lee ◽  
Patrick A. McKee

Abstract The primary inhibitor of plasmin, α2-antiplasmin (α2AP), is secreted by the liver into plasma with Met as the amino-terminus. During circulation, Met-α2AP is cleaved by antiplasmin-cleaving enzyme (APCE), yielding Asn-α2AP, which is crosslinked into fibrin approximately 13 times faster than Met-α2AP. The Met-α2AP gene codes for either Arg or Trp as the sixth amino acid, with both polymorphic forms found in human plasma samples. We determined the Arg6Trp genotype frequency in a healthy population and its effects on Met-α2AP cleavage and fibrinolysis. Genotype frequencies were RR 62.5%, RW 34.0%, and WW 3.5%. The polymorphism related to the percentage of Met-α2AP in plasma was WW (56.4%), RW (40.6%), and RR (23.6%). WW plasma tended to have shorter lysis times than RR and RW plasmas. APCE cleaved purified Met-α2AP(Arg6) approximately 8-fold faster than Met-α2AP(Trp6), which is reflected in Asn-α2AP/Met-α2AP ratios with time in RR, RW, and WW plasmas. Removal of APCE from plasma abrogated cleavage of Met-α2AP. We conclude that the Arg6Trp polymorphism is functionally significant, as it clearly affects conversion of Met-α2AP to Asn-α2AP, and thereby, the rate of α2AP incorporation into fibrin. Therefore, the Arg6Trp polymorphism may play a significant role in governing the long-term deposition/removal of intravascular fibrin.


Agronomy ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 602 ◽  
Author(s):  
Hayoung Song ◽  
Jong-In Park ◽  
Byung-Ho Hwang ◽  
Hankuil Yi ◽  
HyeRan Kim ◽  
...  

Keeping green leaf color at the time of harvest is one of the important traits for breeding of Brassica oleracea var. capitata f. alba, and this trait is related to low anthocyanin contents. To understand the differential accumulation of anthocyanins in cabbage, we selected high anthocyanin accumulators (HAAs) and low anthocyanin accumulator (LAAs) of cabbages and examined the anthocyanin content and the expression of anthocyanin biosynthesis-related genes. Among many genes investigated, BoDFR1 was found to be closely related to anthocyanin accumulation, even under low temperature (LT) conditions. BoDFR1 sequence analyses between HAAs and LAAs revealed that there is a single nucleotide polymorphism (SNP) (1118T/A) in the coding sequence, which substitutes one amino acid from Leu261 to His261; we named BoDFR1 with His261 substitution as BoDFR1v. This amino acid substitution did not affect dihydroflavonol 4-reductase (DFR) activity and substrate specificity, but the polymorphism showed tight association to the BoDFR1 expression, i.e., high level expression of BoDFR1 and low level expression of BoDFR1v under LT conditions. The high levels of BoDFR1 expression were due to the high levels of BoMYB114 and BobHLH expressions combined with low level expression of BoMYBL2, a repressor MYB. On the other hand, low levels of BoDFR1v expression seemed to be related to very low level expressions of BoMYB114 and BobHLH combined with a high level expression of BoMYBL2. It seems that different expression levels of these regulatory genes for MBW (MYB-bHLH-WD40) complex between HAAs and LAAs regulate BoDFR expression and anthocyanin accumulation. Using a single nucleotide polymorphism (SNP) between BoDFR1 and BoDFR1v, molecular markers for PCR and high resolution melt analyses were developed and validated to distinguish between HAAs and LAAs. Combined use of the BoDFR1 SNP marker with other stress markers, such as a cold tolerant marker, will greatly improve cabbage breeding.


2007 ◽  
Vol 82 (20) ◽  
pp. 10318-10320 ◽  
Author(s):  
W. W. Laegreid ◽  
M. L. Clawson ◽  
M. P. Heaton ◽  
B. T. Green ◽  
K. I. O'Rourke ◽  
...  

ABSTRACT Variation in the ovine prion protein amino acid sequence influences scrapie progression, with sheep homozygous for A136R154Q171 considered susceptible. This study examined the association of survival time of scrapie-exposed ARQ sheep with variation elsewhere in the ovine prion gene. Four single nucleotide polymorphism alleles were associated with prolonged survival. One nonsynonymous allele (T112) was associated with an additional 687 days of survival for scrapie-exposed sheep compared to M112 sheep (odds ratio, 42.5; P = 0.00014). The only two sheep homozygous for T112 (TARQ) did not develop scrapie, suggesting that the allelic effect may be additive. These results provide evidence that TARQ sheep are genetically resistant to development of classical scrapie.


Blood ◽  
2010 ◽  
Vol 115 (10) ◽  
pp. 2073-2076 ◽  
Author(s):  
Brian R. Curtis ◽  
Nancy J. Cox ◽  
Mia J. Sullivan ◽  
Anuar Konkashbaev ◽  
Krista Bowens ◽  
...  

Abstract The molecular basis of the HNA-3a/b (5b/a) leukocyte antigen system has not yet been defined despite evidence that HNA-3a–specific antibodies are particularly prone to cause severe, often fatal, transfusion-related lung injury. We used genome-wide single nucleotide polymorphism scanning and sequencing of DNA from persons of different HNA-3a/b phenotypes to identify a single single nucleotide polymorphism in exon 7 of the CLT2 gene (SLC44A2) that predicts an amino acid substitution in the first extracellular loop of choline transporter-like protein 2, a member of the choline transporter-like protein family of membrane glycoproteins, and correlates perfectly with HNA-3a/b phenotypes (R154 encodes HNA-3a; Q154 encodes HNA-3b). Mass spectrometric analysis of proteins immunoprecipitated from leukocytes by anti–HNA-3a provided direct evidence that anti–HNA-3a recognizes choline transporter-like protein 2. These findings will enable large-scale genotyping for HNA-3a/b to identify blood donors at risk to have HNA-3a–specific antibodies and should facilitate development of practical methods to detect such antibodies and prevent transfusion-related lung injury.


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