意大利的科学家日前称,他们最近在罗马的一座千年古墓中新发现了两种极其罕见的细菌。这两种细菌此前人类从来没有发现过,对于研究生物进化史具有重要的意义。
在最新一期出版的《国际系统与进化微生物学》(IJSEM)杂志上,意大利科学家公布了他们的这一最新发现。许多细菌生存于地下墓穴的墙壁之上,正是这些细菌导致了许多历史建筑的腐朽和损坏。近日,意大利墨西拿大学科学家在对圣卡利斯督墓窟的考古过程中,在墓窟腐朽的墓壁表面发现了两种新的微生物。圣卡利斯督墓窟是一个位于罗马占地37英亩的大型墓地的一部分。墓窟建造于二世纪末期,以教皇卡利斯督一世的名字而命名。历代教宗,自泽弗利诺起,至欧提基安止(除高尔内略和加利斯督两位教宗外),共有30多位教皇或殉教者埋葬在该墓窟。
科学家们从墓穴的绿锈中或墓壁涂层中分离出两种新的细菌。新发现的细菌均是克里贝拉属,并被分别命名为克里贝拉-卡塔克姆贝(Kribbella catacumbae)和克里贝拉-桑克提卡利斯提(Kribbella sancticallisti)。克里贝拉属类最早发现于1999年。
科学家希望通过对这两种新细菌的研究,能够找到挽救古墓及其他历史建筑的方法,从而避免历史文化遗产被细菌腐蚀和破坏。此外,新物种的发现,也可以帮助人类进一步了解微生物的进化过程。墨西拿大学科学家克莱拉-厄兹介绍,“墓穴的特殊条件允许一些物种的单独进化。实际上,我们此次所发现的克里贝拉属的两个不同物种,其标本采集地之间距离非常接近。这表明,在某种小环境中即使出现一点轻微的条件变化,都有可能导致细菌分别向不同的方向进化。”
“谁要是干扰了法老的安宁,死亡就会降临到他的头上”。这是古埃及第十八王朝法老图坦卡蒙国王的陵墓上镌刻的墓志铭。科学家一直认为,是坟墓中隐藏的病菌导致了进入者的死亡。1999年德国微生物学家哥特哈德-克拉默就曾在木乃伊身上发现了足以致命的细菌孢子(有的生物身体长成以后能产生一种细胞,这种细胞不经过两两结合,就可以直接形成新个体,这种细胞叫孢子),它在木乃伊身上可以寄居繁殖长达数个世纪之久。在得知这一重大医学发现之后,埃及科学家哈瓦斯每次发掘陵墓时都要在墓室墙壁上钻一个通气孔,等陵墓内的腐败空气向外排放数小时之后再进入。由于经验丰富,在过去30年职业生涯里,哈瓦斯虽然屡屡“惊动法老神灵”,可时至今日他依然健在。(生物谷Bioon.com)
生物谷推荐原始出处:
Int J Syst Evol Microbiol 58 (2008), 2090-2097; DOI 10.1099/ijs.0.65613-0
Kribbella catacumbae sp. nov. and Kribbella sancticallisti sp. nov., isolated from whitish-grey patinas in the catacombs of St Callistus in Rome, Italy
Clara Urzì1, Filomena De Leo1 and Peter Schumann2
1 Dept of Microbiological, Genetic and Molecular Sciences, University of Messina, Salita Sperone 31, I-98166 Messina, Italy
2 DSMZ-German Collection of Microorganisms and Cell Cultures GmbH, Inhoffenstrasse 7B, D-38124 Braunschweig, Germany
Several nocardioform actinomycetes were isolated from tufaceous surfaces with whitish-grey patinas in the catacombs of St Callistus in Rome, Italy. The morphology of the isolates and their chemotaxonomic characteristics such as LL-diaminopimelic acid in the cell-wallpeptidoglycan, the major menaquinone of MK-9(H4), phosphatidylinositol, phosphatidylcholine, phosphatidylglycerol and diphosphatidylglycerol as the major polar lipids, as well as complex cellular fatty acid patterns with anteiso-C15 : 0, iso-C16 : 0 and iso-C15 : 0 as predominating components, were in agreement with their classification as members of the genus Kribbella by 16S rRNA gene sequence analysis. The isolates fell into two clusters as revealed by their ribosomal intergenic spacer, RiboPrint and cellular fatty acid patterns and by their MALDI-TOF mass spectra. The two clusters were represented by the strains BC631T and BC633T which shared 97.9 % 16S rRNA gene sequence similarity. Strain BC631T represented a cluster of yellow pigmented strains and was a phylogenetic neighbour ofKribbella koreensis DSM 17837T (gene sequence similarity 98.0 %), while strain BC633T was related to Kribbella flavida DSM 17836T andKribbella karoonensis DSM 17344T (gene sequence similarities of 98.8 % and 98.6 %, respectively). Strains BC631T and BC633T could be differentiated from each other and from their closest phylogenetic neighbours by phenotypic characteristics and DNA–DNA relatednessvalues far below 70 %. It is concluded that the two new strains represent two novel species, for which the names Kribbella catacumbaesp. nov. (type strain BC631T=DSM 19601T=JCM 14968T) and Kribbella sancticallisti sp. nov. (type strain BC633T=DSM 19602T=JCM 14969T) are proposed.