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Introduction: Helicobacter pylori (H. pylori) infection is endemic in Africa. It is a major aetiological factor in the development of peptic ulcer disease and distal gastric cancers. Existing data shows that clinical outcomes are dependent on the virulence of the infecting strain, host´s susceptibility, and environmental factors. In Ghana, a previous study showed that the majority of symptomatic individuals harboured cagA and vacA virulent strains. The main objective of this study was to characterize and assess the significance of other virulence factors, specifically iceA and babA2 in Ghana. Methods: H. pylori iceA and babA2 genes were investigated in dyspeptic patients at the Korle Bu Teaching Hospital (KBTH), Accra, Ghana. The study employed a cross-sectional design consecutively recruiting patients with upper gastrointestinal symptoms for endoscopy. Nucleic acid was extracted from gastric biopsies using a commercial kit (QIAGEN DNeasy tissue kit). H. pylori babA2 and iceA genes were amplified using extracted deoxyribonucleic acid (DNA) and primers by polymerase chain reaction (PCR). Results: majority, (71.1%), of the study participants, were H. pylori positive when tested with urease-campylobacter-like organism (CLO). In total, 46 H. pylori urease CLO-positive samples were randomly analyzed by PCR for iceA, of which, 12 (26%) and 7 (15%) were found to have iceA1 and iceA2 respectively. Of the CLO-positive samples, 9 were randomly analysed for babA2 by PCR. Three samples were babA2 positive and 6 were babA2 negative. Conclusion: in Ghana, although H. pylori is endemic, iceA prevalence is rather low and probably exerts a limited effect on bacterial virulence. Further evaluation would be required, not only to determine association with other virulence factors but more importantly, inter-relationships with wider host and environmental factors that impact on disease pathogenesis.

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We explored the clinical-stage association of gastric intestinal metaplasia (IM) compared to cases of chronic non-atrophic gastritis (CNAG) and its relationship with virulence genotypes of Helicobacter pylori (H. pylori) clinical isolates from patients with dyspepsia in Peru. This study was cross-sectional and included 158 H. pylori clinical isolates; each isolate corresponded to a different Peruvian patient, genotyped by polymerase chain reaction to detect cagA gene and EPIYA motifs, the vacA gene (alleles s1, s2, i1, i2, d1, d2, m1, m2 and subtypes s1a, s1b and s1c), the iceA gene (alleles 1 and 2), and the babA gene (allele 2). We observed that 38.6% presented with IM and that all clinical isolates were CagA positive. The EPIYA-ABC motif was predominant (68.4%), and we observed a high frequency for the vacA gene alleles s1 (94.9%), m1 (81.7%), i1 (63.9%), and d1 (70.9%). Strains with both iceA alleles were also detected (69.6%) and 52.2% were babA2 positive. In addition, it was observed that the cagA+/vacAs1m1 (PR: 2.42, 1.14 to 5.13, p < 0.05) and cagA+/vacAs1am1 (PR: 1.67, 1.13 to 2.45, p < 0.01) genotypes were associated with IM. Our findings revealed the cagA and vacA risk genotypes predominance, and we provided clinically relevant associations between Peruvian patients with H. pylori infection and IM clinical stage.

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We explore both the static and dynamic connectedness across traditional and unconventional assets classes using the Baruník-Krehlík connectedness and wavelets techniques. These techniques are used to characterise the static and rolling-window connectedness of 12 conventional assets and Non-Fungible Tokens (NFT), Index On Cryptocurrency Environmental Attention (ICEA) and Central Bank Digital Currency (CBDC) attention indices. Between January 25, 2010 and July 11, 2022, the wavelet multiple correlations showed increasing high levels of correlation through short-to long-terms; with DJI and SP500 dominanting with the tendency to lead or lag in the short-term. The Baruník-Krehlík technique also showed that spillover is higher at short-terms and gradually decreases across the periods. We also report a pair-specific, frequency-dependent connectedness across the assets and indices. Primarily, we show that Non-Fungible Tokens Attention Index (NFTAI) has a higher frequency-based time-varying spillover across assets than CDBC and ICEA. Regulators need to pay close attention to NFTs because they are not fungible and interchangeable neither can their ownership be transferred.

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We study the dynamic connectedness between green bonds and the cryptocurrency environmental attention index (ICEA), using the TVP-VAR methodology. The spillovers increase with the level of environmental attention, suggesting cross-market activism by green investors. Denmark, the Euro area, Hong Kong, Australia, and the US are the source of spillovers, while Japan, the UK, and Switzerland are major recipients. The return spillovers exceed volatility spillovers and rise in strength during COVID-19 and the geopolitics-induced military hostilities in Ukraine. Several imperative implications of the findings are notable for policymakers, market participants, and practitioners.

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BACKGROUND: Helicobacter pylori cause a variety of gastric malignancies, gastric ulcers, and cause erosive diseases. The extreme nature of the bacterium and the implantation of this bacterium protects it against designing a potent drug against it. Therefore, employing a precise and effective design for a more safe and stable antigenic vaccine against this pathogen can effectively control its associated infections. This study, aimed at improving the design of multiple subunit vaccines against H. pylori, adopts multiple immunoinformatics approaches in combination with other computational approaches. RESULTS: In this regard, 10 HTL, and 11 CTL epitopes were employed based on appropriate adopted MHC binding scores and c-terminal cut-off scores of 4 main selected proteins (APO, LeoA, IceA1, and IceA2). An adjuvant was added to the N end of the vaccine to achieve higher stability. For validation, immunogenicity and sensitization of physicochemical analyses were performed. The vaccine could be antigenic with significantly strong interactions with TOLK-2, 4, 5, and 9 receptors. The designed vaccine was subjected to Gromacs simulation and immune response prediction modelling that confirmed expression and immune-stimulating response efficiency. Besides, the designed vaccine showed better interactions with TLK-9. CONCLUSIONS: Based on our analyses, although the suggested vaccine could induce a clear response against H. pylori, precise laboratory validation is required to confirm its immunogenicity and safety status.

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Helicobacter pylori is one of the most common bacteria affecting human societies worldwide, and is mainly associated with gastrointestinal complications due to different virulence factors. This study aimed to investigate some virulence genes of H. pylori in gastric biopsies of patients with gastritis in Sari city, North of Iran. Informed consent forms were obtained from the studied patients, and those who needed endoscopy were included in the study. To evaluate the prevalence of cagA, iceA1, iceA2, vacA, dupA, and oipA genes, gastric biopsies with positive or negative rapid urease test were collected from 50 patients (25 in each group) with gastro-duodenal diseases. The bacterial DNAs were extracted by a specific kit, and the presence of the genes was analyzed by PCR using specific primers. Eighteen (72%) biopsies from 25 H. pylori-positive samples were cagA-positive, while 17 (68%) biopsies contained the vacA gene, and 11 (44%) samples had both vacA and cagA genes. However, 16 (64%), 12 (48%), 13 (52%), and 14 (56%) biopsies contained dupA, iceA1, iceA2, and oipA genes, respectively. Due to the significant role of the studied virulence factors in the pathogenicity of H. pylori, the high prevalence of these factors in biopsies of patients with gastritis is a concern needing to the management in this region.

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Helicobacter pylori is a pathogenic bacterium that causes gastric ulcers and cancer. Among the diverse virulence genes of H. pylori, the IceA gene was identified to be expressed upon adherence to host cells. The IceA gene has two alleles, iceA1 and iceA2, which encode completely different proteins. IceA1 protein was shown to exert endonuclease activity, whereas IceA2 has never been analyzed at the molecular level. Based on a sequence analysis, IceA2 proteins differ in length depending on the strain and are classified into five groups (A-E). To structurally characterize IceA2, we determined the crystal structure of group-D IceA2 (IceA2sD) and performed a modeling-based comparative analysis of IceA2 groups. IceA2sD consists of three ß-sheet repeats and serially arranges them like the ß-propeller structure of the WD40 domain. However, each ß-sheet of IceA2 is stabilized using a unique structural motif that is not observed in WD40. Moreover, IceA2sD lacks an additionally appended ß-strand and does not form the Velcro-like closure of WD40. Therefore, IceA2sD adopts a curved rod-like structure rather than an enclosed circular structure in WD40. IceA2 proteins contain 1-4 ß-sheet modules depending on the groups and are modeled to be highly diverse in size and shape.

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Helicobacter pylori is a major human pathogen that causes a wide range of gastrointestinal pathology. Progression of H. pylori induced gastritis to more severe disease has been found to highly correlate with the array of virulence factors expressed by the pathogen. The objective of this study was twofold: first, to characterize the genetic diversity of H. pylori strains isolated from 41 non-atrophic gastritis patients in Switzerland, an issue that has not been investigated to date. And second, to assess the prevalence and sequence variation of H. pylori virulence factors (cagA, vacA, iceA and dupA) and genes encoding outer membrane proteins (OMPs; babA, babB, sabA, sabB, hopZ, hopQ and oipA) by whole genome sequencing (WGS) using an Illumina MiSeq platform. WGS identified high genetic diversity in the analyzed H. pylori strains. Most H. pylori isolates were assigned to hpEurope (95.0%, 39/41), and the remaining ones (5.0%, 2/41) to hpEastAsia, subpopulation hspEAsia. Analysis of virulence factors revealed that 43.9% of the strains were cagA-positive, and the vacA s1 allele was detected in 56.0% of the isolates. The presence of cagA was found to be significantly associated (P < 0.001) with the presence of vacA s1, babA2 and hopQ allele 1 as well as expression of oipA. Moreover, we found an association between the grade of gastritis and H. pylori abundance in the gastric mucosa, respectively and the presence of cagA, vacA s1 and hopQ allele 1. Among our 41 gastritis patients, we identified seven patients infected with H. pylori strains that carried a specific combination of virulence factors (i.e., cagA, vacA s1 allele and babA2 allele), recently implicated in the development of more severe gastrointestinal pathology, like peptic ulcer disease and even gastric cancer. To this end, WGS can be employed for rapid and detailed characterization of virulence determinants in H. pylori, providing valuable insights into the pathogenic capacity of the bacterium. This could ultimately lead to a higher level of personalized treatment and management of patients suffering from H. pylori associated infections.

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The aim of this study was to investigate genetic diversity of Helicobacter pylori virulence markers to predict clinical outcome as well as to determine an antibiotic susceptibility of H. pylori strains in Poland. Gastric biopsies from 132 patients with gastrointestinal disorders were tested for presence of H. pylori with the use of rapid urease test, microbial culture, and polymerase chain reaction (PCR) detection. The genetic diversity of 62 H. pylori positive samples was evaluated by detection of cagA and PCR-typing of vacA and iceA virulence-associated genes. Most common H. pylori genotypes were cagA(+)vacAs1m2 (27.4%) and cagA(-)vacAs2m2 (24.2%). In logistic regression analysis, we recognized the subsequent significant associations: gastritis with ureC, i.e., H. pylori infection (p = 0.006), BMI index (p = 0.032); and negatively with iceA1 (p = 0.049) and peptic ulcer with cagA (p = 0.018). Thirty-five H. pylori strains were cultured and tested by E-test method showing that 49% of strains were resistant to at least one of the tested antibiotics. This is the first study that reports the high incidence and diversity of allelic combination of virulence genes in gastroduodenitis patients in Poland. Genotyping of H. pylori strains confirmed the involvement of cagA gene and vacAs1m1 genotype in development and severity of gastric disorder.

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Background: The data about the association between Helicobacter pylori putative virulence factors; iceA and jhp0562/ß-(1,3)galT with clinical outcomes are still controversial. We identified and analyzed two putative H. pylori virulence factors in Nepalese strains. Methods: The iceA and jhp0562/ß-(1,3)galT allelic types were determined by polymerase chain reaction amplification. Histological analysis were classified according to the updated Sydney system and the Operative Link on Gastritis Assessment (OLGA) system. Results: Among 49 strains, iceA1 negative/iceA2 positive (iceA2-positive) was predominant type (57.1%, 28/49) and 20 (40.8%) were iceA1 positive/iceA2 negative. The remaining one (2.0%) was positive for both iceA1 and iceA2 (iceA1/iceA2-mixed). Patients infected with iceA1-positive strains tended to be higher OLGA score than iceA2-positive strains [1.45 [1] vs. 0.07 [0.5], P = 0.09, respectively). The jhp0562 negative/ß-(1,3)galT positive was predominant type (25/51, 49.0%), followed by double positive for jhp0562/ß-(1,3)galT (15/51, 29.4%) and jhp0562 positive/ß-(1,3)galT negative (11/51, 21.6%). Activity in the corpus was significantly higher in jhp0562 negative/ß-(1,3)galT positive than double positive of jhp0562/ß-(1,3)galT positive [mean (median); 1.24 (1) vs. 0.73 (1), P = 0.03]. There was association between iceA and subtype of vacA signal region (e.g., s1a, s1b or s1c) and combination subtypes of signal and middle regions (e.g., s1a-m1c) (P = 0.02, r = 0.29; and P = 0.002, r = 0.42, respectively). In addition, jhp0562/ß-(1,3)galT genotypes associated with cagA pre-EPIYA type (e.g., 6 bp-, 18 bp-, or no deletion-type) (P = 0.047, r = 0.15). Conclusion: The inconsistency results of the association between iceA, jhp0562/ß-(1,3)galT and histological scores suggesting that these genes may associate with genetic heterogeneity rather than as a true virulence factor.

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BACKGROUND: The complex pathogenesis of Helicobacter pylori (H. pylori) and the features of the host influence the diverse clinical outcomes. A mass of studies about virulence genes have accelerated the exploration of pathogenesis of H. pylori infection. Induced by contact with epithelium gene A (iceA) is one of the biggest concerned virulence genes. In this study, we explored the relationship between iceA and the magnitude of the risk for clinical outcomes and the prevalence of iceA-positive H. pylori in People's Republic of China and other countries. METHODS: We searched the electronic databases of PubMed, Embase, CNKI, VIP, and Wanfang by literature search strategy. The studies conforming to the inclusion criteria were assessed. With these data, we systematically analyzed the relationship between the iceA gene of H. pylori and clinical outcomes. RESULTS: Nineteen articles with 22 studies, a total of 2,657 cases, were involved in the study. The iceA1 gene was significantly associated with peptic ulcer disease (odds ratio =1.28, 95% confidence interval =1.03-1.60; P=0.03), especially in People's Republic of China (odds ratio =1.40, 95% confidence interval =1.07-1.83; P=0.01). Moreover, the prevalence of iceA1 was significantly higher than iceA2 in People's Republic of China (P<0.0001). The prevalence of both iceA1 and iceA2 was significantly different (P<0.0001) in People's Republic of China and in other countries. CONCLUSION: The system analysis showed that infection with the iceA1-positive H. pylori significantly increased the overall risk for peptic ulcer disease, especially in People's Republic of China. The iceA2 gene status and clinical outcome of H. pylori infection have no significant correlation. H. pylori iceA1 genotype is the major epidemic strain in People's Republic of China.

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We studied the prevalence of Helicobacter pylori virulence markers, e.g. cytotoxin associated gene (cagA), cagA promoter, vacuolating associated cytotoxin A (vacA) alleles induced by contact with epithelium (iceA type), and outer membrane protein Q (hopQ) in expatriates and compared them with those in local residents. Gastric biopsies were obtained at endoscopy for culture, histology and PCR for virulence marker and hopQ. Of 309 patients, 236 (76%) were males with a mean age of 45 years. A total of 102 patients were expatriates. hopQ type 1 was present in 98 (47%) local residents compared to 88 (86%) expatriates (P < 0·001), while hopQ type 2 was present in 176 (85%) local residents, compared to 60 (59%) expatriates (P < 0·001). H. pylori virulence marker cagA was positive in 97 (47%) local residents compared to 86 (84%) expatriates (P < 0·001) while cagA-P was positive in 72 (35%) local residents compared to 87 (85%) expatriates (P < 0·001). iceA type 1 was positive in 157 (76%) local residents compared to 45 (44%) expatriates (P < 0·001), while iceA type 2 was positive in 81 (39%) local residents compared to 86 (84%) expatriates (P < 0·001). Distribution of H. pylori cagA, cagA promoter, iceA and hopQ type in local residents and expatriates was different. H. pylori virulence markers were associated with severe pathology in expatriates.

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AIM: To investigate the diversity of Helicobacter pylori (H. pylori) genotypes and correlations with disease outcomes in an Iranian population with different gastroduodenal disorders. METHODS: Isolates of H. pylori from patients with different gastroduodenal disorders were analyzed after culture and identification by phenotypic and genotypic methods. Genomic DNA was extracted with the QIAamp DNA mini kit (Qiagen, Germany). After DNA extraction, genotyping was done for cagA, vacA (s and m regions), iceA (iceA1 , iceA2 ) and babA with specific primers for each allele using polymerase chain reaction (PCR). All patients' pathologic and clinical data and their relation with known genotypes were analyzed by using SPSS version 19.0 software. χ² test and Fisher's exact test were used to assess relationships between categorical variables. The level of statistical significance was set at P < 0.05. RESULTS: A total of 71 isolates from 177 patients with different gastroduodenal disorders were obtained. Based on analysis of the cagA gene (positive or negative), vacA s-region (s1 or s2), vacA m-region (m1 or m2), iceA allelic type (iceA1 and iceA2 ) and babA gene (positive or negative), twenty different genotypic combinations were recognized. The prevalence of cagA, vacA s1 , vacA s2 , vacA m1 , vacA m2 , iceA1 , iceA2 , iceA1+iceA2 and babA were 62%, 78.9%, 19.7%, 21.1%, 78.9%, 15.5%, 22.5%, 40.8% and 95.8%, respectively. Interestingly, evaluation of PCR results for cagA in 6 patients showed simultaneous existence of cagA variants according to their size diversities that proposed mixed infection in these patients. The most prevalent genotype in cagA-positive isolates was cagA⁺/vacAs1m2 /iceA1 +A2 /babA+ and in cagA-negative isolates was cagA⁻/vacAs1m2 /iceA-/babA+. There were no relationships between the studied genes and histopathological findings (H. pylori density, neutrophil activity, lymphoid aggregation in lamina propria and glandular atrophy). The strains which carry cagA, vacAs1/m1 , iceA2 and babA genes showed significant associations with severe active chronic gastritis (P = 0.011, 0.025, 0.020 and 0.031, respectively). The vacAs1 genotype had significant correlation with the presence of the cagA gene (P = 0.013). Also, babA genotype showed associations with cagA (P = 0.024). In the combined genotypes, only cagA⁺/vacAs1m1 /iceA2 /babA+ genotype showed correlation with severe active chronic gastritis (P = 0.025). CONCLUSION: This genotyping panel can be a useful tool for detection of virulent H. pylori isolates and can provide valuable guidance for prediction of the clinical outcomes.

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PURPOSE: To investigate the relation of the gastric epithelial cell proliferation, apoptosis and genotypes of H. pylori in children. METHODS: Histologic grading by updated Sydney system, PCNA immunostaining, TUNEL method and the genotypes (cagA, picB and iceA) by PCR were performed in H. pylori positive (N=20) and negative (N=20) gastric biopsy specimens. RESULTS: PCNA index was significantly different between H. pylori positive children (77.4+/-13.12) and H. pylori negative children (52.3+/-12.20) (p=0.000). There were positive correlations between PCNA index and H. pylori density (r=0.624, p=0.000), polymorphonuclear neutrophil activity (r=0.460, p=0.005) and chronic inflammation (r=0.433, p=0.009). Apoptosis index of H. pylori positive children (0.70+/-0.411) was significantly higher than of H. pylori negative children (0.14+/-0.201) (p=0.000). Positive correlations between apoptosis index and H. pylori density (r=0.691, p=0.000), polymorphonuclear neutrophil activity (r=0.585, p=0.000) and chronic inflammation (r=0.535, p=0.001) were noted. As PCNA index increased, apoptosis index significantly increased (r=0.527, p=0.001). The positive rates of genotypes were cagA 90%, picB 75%, iceA1 60% and iceA2 15%, respectively. There were no significant correlations between the status of the genotypes and PCNA index, apoptosis index, the endoscopic findings and the histologic findings. CONCLUSION: PCNA index and apoptosis index in H. pylori positive children were higher than in H. pylori negative children but were not related to H. pylori genotypes. This study suggested that correlatively increased gastric epithelial cell proliferation and apoptosis are important to pathogenesis of H. pylori infection in children.

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PURPOSE: The H. pylori cagA gene, vacA gene and iceA gene are considered to be important virurence factors that have been implicated in the development of gastric adenocarcinoma. It was reported that the presence of IS605 elements may be responsible for rearrangements and lead to partial or total deletions of the cag pathogenicity island (PAI) and the virulence of cag PAI may be changed. However, different results regarding the association between these virulence factors and clinical disease have been reported from different geographic regions. This study evaluated the relationship between H. pylori virulence factors such as cagA, vacA, iceA, IS605 and gastric adenocarcinoma. MATERIALS AND METHODS: H. pylori isolates were obtained from 54 infected patients (24 cases of gastric adenocarcinoma, 30 cases of control). H. pylori isolates were identified by PCR with ureC gene and 16S rRNA. PCR was performed to examine cagA, vacA, iceA and IS605 genotypes. RESULTS: Significant difference was found in the negative rates of cagA between gastric adenocarcinoma group and control (62.5% vs. 33.3% P=0.033). No significant difference was found in the prevalence of iceA, vacA between gastric adenocar cinoma and control. The genotype of cagA+ vacA s1-m1 iceA1 was predominant in H. pylori isolates irrespective of the clinical outcome. IS605 in PAI was not found in gastric adenocarcinoma gruop and control. The positive rates of IS605 in genome were 33.3% in gastric adenocarcinoma group and 36.7% in control (P>0.05). In gastric carcinoma, the positive rate of cagA+/IS605- was lower than in control (12.5% vs. 40.0%, P=0.025) and the positive rate of cagA-/IS605- was higher than in control (54.2% vs. 23.3%, P=0.02). CONCLUSION: H. pylori virulence factors had not related significantly with gastric adenocarcinoma. Further study is needed to examine the specificity of H. pylori strains.

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The genetic status of cagA, vacA subtype, iceA1, and babA, and the relationship to gastroduodenal diseases were assessed in Helicobacter pylori isolates in Korea. Seventy-six strains of H. pylori were isolated from the antrum and the corpus of 41 adult patients (22 with peptic ulcer and 19 with gastritis). The cagA, iceA1, and babA genes were assessed by polymerase chain reaction and the vacA subtypes were determined by reverse hybridization-line probe assay. The positive rates of 349-bp cagA, 208-bp cagA, iceA1, and babA genes were 97.4%, 96.1%, 84.2%, and 36.1%, respectively. The vacA s1a, s1b, s1c, and s2 variants were detected in 11.8%, 3.9%, 80.4%, and 1.3%, respectively. m1 (78.9%) is more prevalent than m2 (5.3%). The most common vacA genotype was s1c/m1 (61.9%), and 14 isolates (18.4%) contained mixed vacA genotypes from a single biopsy specimen. Twenty-one (60%) of 35 patients were infected with more than two strains of different cagA, iceA1, babA, and vacA genotypes. None of cagA, iceA1, babA, and vacA s1/m1 were associated with peptic ulcer. In conclusion, most H. pylori isolates in Korea carry cagA, iceA1, and vacA s1c/m1 genes, and reside with multiple strains. These genes do not correlate with the peptic ulcer in the Korean patients.

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Objective To determine the distribution of Helicobacter pylori (H.pylori) iceA, babA2 in patients in Shanghai and explore the association of H. pylori strain genotype with its clinical outcome after infection. Methods A total of 141 H. pylori strains was isolated from gastric biopsy samples of 43 patients with chronic gastritis, 47 patients with duodenal ulcer (DU), 30 patients with gastric ulcer(GU) and 21 patients with non cardia gastric carcinoma. The iceA, vacA, cagA, and babA2 genotypes were determined by polymerase chain reaction (PCR). Results iceA1, iceA2 and babA2 were detected in 74.5% (105/141) , 15.6% (22/141) and 63.8% (90/141) of the 141 H.pylori strains, respectively, while 2 of isolated H. pylori strain (1.4%) were positive for both iceA alleles and 16(11.3%) were negative for both iceA alleles. The prevalence of babA2 and the combined genotype of babA2 and cagA in H. pylori isolated from DU patients were significantly higher than that in GU patients (74.5% vs. 50.0% for babA2, P =0.028; 70.2% vs. 46.7% for babA2 and cagA, P =0.039). There was no significant difference in prevalence of babA2 among other disease groups. No association of different clinical diseases with iceA genotype was detected. Conclusions The most common genotype of H.pylori strains isolated from patients in Shanghai is iceA1 +/babA2 +. babA2 may play different role in the pathogenesis of duodenal ulcer and gastric ulcer. No association between iceA status and clinical outcome of H.pylori infection was confirmed in our study.

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Using the chromosomal DNA of an ice nucleation active bacterium Erwinia ananas 110 as template, an ice nucleation active (ina) gene was amplified by PCR with Taq plusI DNA polymerase. After sequencing and compared with reported ina genes, the cloned gene was identified as a new ina gene and was registered in GenBank at the accession number of AF387802. The new ina gene, named as iceA, has 3921 bp for its coding region, which encodes 1306 amino acids consisting of repetitive segment (R-domain, 1104aa), which is flanked by N-and C-terminal sequences, with 161 aa and 41aa, respectively.