Talk:Avery–MacLeod–McCarty experiment/GA1

GA Review

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I'll be reviewing this article; this stuff is right up my alley! Sasata (talk) 17:42, 22 February 2009 (UTC)

GA review (see here for criteria)

1. It is reasonably well written.

   a (prose): b (MoS):

   Prose is generally fine, although a light copyedit is needed. Extra wikilinking is suggested. A few MOS fixes are recommended. All good now. Sasata (talk) 06:04, 26 February 2009 (UTC)

2. It is factually accurate and verifiable.

   a (references): b (citations to reliable sources): c(OR):

   I'd really like to see citations to all of the original classic experiments that are referred to. The article also needs several citations to verify OR-sounding parts. Done. Sasata (talk) 06:04, 26 February 2009 (UTC)

3. It is broad in its coverage.

   a (major aspects): b (focused):

   I'd like to see some more background to establish context, especially more detail about the Griffith experiment that ultimately led to this experimental discovery. The new background section is great and gives readers historical context. Sasata (talk) 06:04, 26 February 2009 (UTC)

4. It follows the neutral point of view policy.

   Fair representation without bias:

5. It is stable.

   No edit wars etc.:

6. It is illustrated by images, where possible and appropriate.

   a (images are tagged and non-free images have fair use rationales): b (appropriate use with suitable captions):

   Suggest to add photos of researchers. Done. Sasata (talk) 06:04, 26 February 2009 (UTC)

7. Overall:

   Pass/Fail:

Citations (or lack of) are the major issue with the article. In the context of GA, more is better; a single citation at the end of the paragraph isn't sufficient. Don't be afraid to cite a sentence, and then the next sentence, even if the source is on the same page as the citation in the last sentence. If this isn't done, there's the danger that future editors will add information or move stuff around, and the fact loses contact with its source. Am failing the article for now, but am confident that implementation of the suggested improvements will help the article meet GA criteria. Sasata (talk) 05:21, 25 February 2009 (UTC)

I failed this prematurely the first time, and am glad to fix my error by promoting this interesting and important article. Sasata (talk) 06:04, 26 February 2009 (UTC)

Comments

Lead

• Wikilink virulence
  • Done.--ragesoss (talk) 19:09, 25 February 2009 (UTC)

Experimental work

• The first sentence of this next section starts "After Griffith's experiment...". I think a little more explanation of the background leading up to the AMM experiment would be beneficial to the reader. For example, I don't find any obvious explanation of what bacterial transformation is; yes, it's wikilinked in the first sentence of the lead, but since the experiment is about transformation, I would expect it be be explained here without have to read background elsewhere. I would also like to read more details about the 1928 Griffith experiment (mentioned prominently in the lead, but not so much in the article).
  • I've created a background section that deals with this.--ragesoss (talk) 19:09, 25 February 2009 (UTC)

• "... the different types are classified according to their immunological specificity." Please clarify/define immunological specificity for a reader who might not know what this means. This will help them understand "immunological precipitation" and "type-specific antibodies" in the next paragraph.
  • I did my best to explain this in the new background section.--ragesoss (talk) 19:09, 25 February 2009 (UTC)

• "The purification procedure consisted of first killing the bacteria with heat and extracting the saline-soluble components, then precipitating out the protein using chloroform and hydrolyzing the polysaccharide capsules with an enzyme, using an immunological precipitation caused by type-specific antibodies to verify the complete destruction of the capsules." Suggest splitting into two sentences.
  • Done.--ragesoss (talk) 19:09, 25 February 2009 (UTC)

• "Chemical analysis showed that the proportions of carbon, hydrogen, nitrogen, and phosphorus in this active portion were consistent with the chemical composition of DNA"
  • Done.--ragesoss (talk) 19:09, 25 February 2009 (UTC)

• wikilink RNA, protein, nucleotide base
  • Done.--ragesoss (talk) 19:09, 25 February 2009 (UTC)

• "...They found that trypsin, chymotrypsin and ribonuclease did not affect it..." briefly mention what these enzymes do for the uninitiated.
  • Done.--ragesoss (talk) 19:10, 25 February 2009 (UTC)

• "...and extremely precise work by Rollin Hotchkiss"
  • I've remove "extremely", although reluctantly, but I'm leaving in "precise". The point here is that analysis that could narrow it down to 0.02% was far more precise than what had been possible with standard techniques before Hotchkiss's work.--ragesoss (talk) 19:09, 25 February 2009 (UTC)

• change .02% to 0.02%
  • Done.--ragesoss (talk) 19:09, 25 February 2009 (UTC)

Reception and legacy

• "The experimental findings of the Avery-MacLeod-McCarty experiment were quickly confirmed, and extended to a number of other bacterial species as well." Source? Examples?
  • I've reworked this to make it clearer and correct a mistake... it was confirmed and extended to other features of pneumococcus, not (until later) other species of bacteria. The sources now are repeated closer.--ragesoss (talk) 02:32, 26 February 2009 (UTC)
• wikilink chromosomes
  • Done.--ragesoss (talk) 02:07, 26 February 2009 (UTC)

• The whole paragraph needs to be better cited, or else it sounds like original research. Eg:

"DNA was therefore thought to be the structural component of chromosomes, whereas the genes were thought likely to be made of the protein component of chromosomes."

"... many biologists thought genes might be a sort of "super-enzyme""

"Furthermore, few biologists thought that genetics could be applied to bacteria,"

" were dismissive of DNA as the genetic material"

• The citations to original papers broke things up so that now the secondary sources that all this comes from are repeated. I also added a general reference for the peripheral issue of theories of the gene and the relationship to enzymes and viruses. It's not referenced for every single sentence, but it should be quite sufficient.--ragesoss (talk) 02:11, 26 February 2009 (UTC)

• "This line of thinking was reinforced by the 1935 crystallization of tobacco mosaic virus by Wendell Stanley," Cite to original paper. Same for "...viruses were shown according to Stanley to be proteins and to share the property of autocatalysis with many enzymes"
  • Done, for the first. There isn't any one original paper for the latter bit, which is an argument Stanley developed in a number of separate publications; instead, a secondary source that ties this stuff together is cited.--ragesoss (talk) 02:13, 26 February 2009 (UTC)

• "the geneticists informally known as the phage group"
  • Done.--ragesoss (talk) 02:07, 26 February 2009 (UTC)

• "Scientists looking back on the Avery-MacLeod-McCarty experiment have disagreed about just how influential it was in the 1940s and early 1950s" Source?
  • This is cited at the end of the paragraph (Deichmann), which is standard practice. I don't think it's necessary or helpful to cite every single sentence in a paragraph when it comes from the same place, cited at the end of the paragraph.--ragesoss (talk) 02:07, 26 February 2009 (UTC)

• "Gunther Stent suggested that it was largely ignored, and only celebrated afterwards—similarly to Gregor Mendel's work decades before the rise of genetics." Source?
  • Likewise, this all comes from Deichmann, cited at the end of the paragraph.--ragesoss (talk) 02:07, 26 February 2009 (UTC)

• "A few microbiologists and geneticists had taken an interest in the physical and chemical nature of genes before 1944, but the Avery-MacLeod-McCarty experiment spurred renewed and wider interest in the subject." Source? Next sentence too. And the one after.
  • Likewise, this all comes from Deichmann, cited at the end of the paragraph.--ragesoss (talk) 02:07, 26 February 2009 (UTC)

• "genetic implications—atas Avery may have"
  • Actually, it was supposed to "that". Fixed.--ragesoss (talk) 02:07, 26 February 2009 (UTC)

• "Biochhemist Erwin Chargaff,"
  • Done.--ragesoss (talk) 02:07, 26 February 2009 (UTC)

• "Between 1944 and 1954, the paper was cited at least 239 times (with citations spread evenly though those years), mostly in papers on microbiology, immunochemistry, and biochemistry." Source?
  • This comes from Deichmann. The citation is now repeated closer to this sentence, because of the addition of primary sources.

• "...the experiment considerable work in microbiology," ??
  • Fixed.--ragesoss (talk) 02:22, 26 February 2009 (UTC)

• "...analogies between bacterial heredity and the genetics andof sexually-reproducing organisms."
  • Done.--ragesoss (talk) 02:22, 26 February 2009 (UTC)

• "French microbiologist André Boivinclaimed to extend Avery's bacterial transformation findings to E. coli," cit to original paper. Next sentence as well.
  • Done.--ragesoss (talk) 02:07, 26 February 2009 (UTC)

• "... showed that genetics could to apply to bacteria,"
  • Done.--ragesoss (talk) 02:07, 26 February 2009 (UTC)

• "Avery's work also may have played a role in the continuation of X-ray crystallography studies of DNA by Maurice Wilkins, in the face of pressure to switch subjects to whole cells." Not sure what is meant by this, please clarify.
  • I reworded this so that it makes sense now, hopefully.--ragesoss (talk) 02:07, 26 February 2009 (UTC)

• "... Avery's work was largely neglected by much of the scientific community." Source?
  • This whole paragraph comes from the same source, and I don't think it's appropriate to repeat the same citation on a per-sentence basis here.--ragesoss (talk) 02:22, 26 February 2009 (UTC)

• Hotckiss -> Hotchkiss
  • Done.--ragesoss (talk) 02:07, 26 February 2009 (UTC)

• "By the appearance of the 1952 Hershey-Chase experiment, " or something like that
  • "time of the", I think, works a little better. Added.--ragesoss (talk) 02:07, 26 February 2009 (UTC)

• "... published his experimental evidence of the absence of protein in Avery's transforming principle in 1952." cit to original paper
  • Done.--ragesoss (talk) 02:07, 26 February 2009 (UTC)

• "...biologists were more inclined to think of heredity in the same terms for bacteria and higher organisms." Source?
  • Cited at the end of that sentence now.--ragesoss (talk) 02:22, 26 February 2009 (UTC)

• Wikilink radioactive isotopes
  • Done.--ragesoss (talk) 02:07, 26 February 2009 (UTC)

• In the Notes section, replace hyphens with ndashes for page ranges.
  • I don't think the gains in appearance outweigh the costs of added even more code to the page and making it even harder to make sense of while editing, but I've done this anyway. Ugh.--ragesoss (talk) 02:39, 26 February 2009 (UTC)

• There's photos of all three scientists at Wiki Commons, I think this article would be an excellent place to use them.
  • Done.--ragesoss (talk) 02:22, 26 February 2009 (UTC)