科學家開發出評估病毒基因組質量和完整性的新工具
作者:
小柯機器人發布時間:2020/12/22 22:27:01
美國勞倫斯伯克利國家實驗室Nikos C. Kyrpides、Stephen Nayfach等研究人員合作開發出評估病毒基因組質量和完整性的新工具。相關論文於2020年12月21日在線發表在《自然—生物技術》雜誌上。
研究人員報導了CheckV,這是一種用於識別封閉的病毒基因組、估計基因組片段的完整性並從整合的原病毒中去除側翼宿主區域的自動化方法。CheckV通過將序列與完整病毒基因組的大型資料庫進行比較來評估完整性,該資料庫包括從對公開可獲得的元基因組、元轉錄組和元病毒組的系統搜索中識別出的76262個病毒基因組。
在對模擬數據集進行驗證並與現有方法進行比較之後,研究人員將CheckV應用到了由元基因組組裝的病毒序列的各種龐大集合中,包括IMG/VR和全球海洋病毒組。這項研究揭示了44,652個高質量的病毒基因組(>90%完整),儘管絕大多數序列是小片段,這突出了從短讀本元基因組中組裝病毒基因組的挑戰。此外,研究人員發現去除宿主汙染大大改善了輔助代謝基因的準確識別和對病毒編碼功能的解釋。
據介紹,數百萬個新的病毒序列已經從元基因組中鑑定出,但是這些序列的質量和完整性差異很大。
附:英文原文
Title: CheckV assesses the quality and completeness of metagenome-assembled viral genomes
Author: Stephen Nayfach, Antonio Pedro Camargo, Frederik Schulz, Emiley Eloe-Fadrosh, Simon Roux, Nikos C. Kyrpides
Issue&Volume: 2020-12-21
Abstract: Millions of new viral sequences have been identified from metagenomes, but the quality and completeness of these sequences vary considerably. Here we present CheckV, an automated pipeline for identifying closed viral genomes, estimating the completeness of genome fragments and removing flanking host regions from integrated proviruses. CheckV estimates completeness by comparing sequences with a large database of complete viral genomes, including 76,262 identified from a systematic search of publicly available metagenomes, metatranscriptomes and metaviromes. After validation on mock datasets and comparison to existing methods, we applied CheckV to large and diverse collections of metagenome-assembled viral sequences, including IMG/VR and the Global Ocean Virome. This revealed 44,652high-quality viral genomes (that is, >90% complete), although the vast majority of sequences were small fragments, which highlights the challenge of assembling viral genomes from short-read metagenomes. Additionally, we found that removal of host contamination substantially improved the accurate identification of auxiliary metabolic genes and interpretation of viral-encoded functions.
DOI: 10.1038/s41587-020-00774-7
Source: https://www.nature.com/articles/s41587-020-00774-7