Probing the viral metallome: searching for metalloproteins in bacteriophage λ– the hunt begins

Abstract

Although the proteome and genome of bacteriophages are well developed, there is little knowledge about metals and their interactions with the phages, even though metals have been observed in stabilizing phage particles. With expanding studies of phage display and its promising applications, metalloprotein investigations in the bacteriophage areas are necessary to understand whether or not metalloproteins are included in the viral coat proteome. Since these virus studies are still in their infancy, lambda phage was chosen due to its high metal-binding potential as suggested by the cysteine/methionine rich proteins in the viral coat. After large-scale preparation and further purification of lambda phage according to standard protocols, state-of-the-art metallomics techniques via combinations of chromatographies and mass spectrometries were utilized for screening metal-associated species in lambda phage. The lambda phage sample was first separated using non-denaturing size exclusion chromatography with selective metal detection by ICPMS for screening associated metals and generating size distribution fractions for the various metal species, some of which include metalloproteins. Various molecular size distribution patterns were exhibited for the metals detected, Mn, Fe, Co, Ni, Cu and Zn, at different molecular weight ranges. On the other hand numerous other metals were not associated with the coat proteins, as they were not detected in the different molecular weight fractions. Further identification for putative metallopeptides and metalloproteins was accomplished by collecting various metal species' fractions offline and subsequently analyzing tryptically-digested fractions via nanoLC-Chip-ESI-MS. By searching appropriate MS databases with both Spectrum Mill and MASCOT search engines, the main capsid protein, gpE, a capsid decoration protein, gpD, and main tail component protein, gpV, were found and are known for associations with the detected transition metals. These findings will likely provide valuable information for lambda phage engineered applications.

Native SDS-PAGE: high resolution electrophoretic separation of proteins with retention of native properties including bound metal ions

“…The limiting problem in applying LA-ICP-MS or other analytical means to detect elements in metallo-proteomic studies has been recognized as the lack of reliable methods to separate the proteome with high resolution while retaining bound metal ions, particularly in the final electrophoresis preceding metal analysis. 13,[49][50][51][52][53][54][55][56][57][58] Others have described methods with modified modifications of conditions of protein electrophoresis that seek to ameliorate the denaturing feature of SDS-PAGE. 15,[59][60][61][62] In regards to the field of metallomics, Finney et al showed the deletion of EDTA to the electrophoretic buffers of SDS-PAGE helped maintain a stable chromium-bovine serum albumin complex as measured by synchrotron X-ray fluorescence.…”

Antiviral surfaces and coatings and their mechanisms of action

“…It has been also documented that the oxidation and oxidative stress such as the addition of peroxide or ascorbate could enhance the biocidal properties of copper 63 . Cu ions can also interact with different viral components, e.g., can cause the inactivation of viral metalloproteins 64,65 by replacing the respective metal with copper 66 . Proteins tend to select divalent metal ions from the environment, following the Irving-Williams order of stability: 67 Mg 2+ < Mn 2+ < Fe 2+ < Co 2+ < Ni 2+ < Cu 2+ > Zn 2+ .…”

Месторождения Стратегических И Редкоземельных Металлов Как Предмет Био-Индикации, Элементологии И Металломики

“…В связи с этим следует отметить принципиальные различия молекулярных форм усвоения металла представителями различных царств и специфику форм и механизмов усвоения в зависимости от таксонов: по этому принципу в анализе первичных ассимилянтов различают, например, металломику хемоавтотрофных микроорганизмов (Basu, 2008;Barton et al, 2007) и металломику растений (Salt, 2013). В то же время, неспецифической фиксацией металлов и, в итоге, собственной вирусной металломикой характеризуют и бактериофагов (Zhang et al, 2011), что рационально, исходя из известной связи между эпигенетикой и металломикой (Wrobel et al, 2009) и наличия содержащих их бактерий в автотрофных сообществах при некоторых формах рудообразования. Характеристической чертой множества подходов металломики является их применимость к палеобиогенному веществу (Edwards et al, 2014), что позволяет говорить об аккумуляционной достоверности данных металломики в аспекте построения палеогеологических карт при учете информации об отсутствии метаморфизирующей активности современных организмов на некотором уровне или регионе интереса (ROI).…”