From sissi_2009 from hotmail.com Mon Mar 2 13:13:15 2009 From: sissi_2009 from hotmail.com (Sissi zhang) Date: Mon Mar 2 17:28:02 2009 Subject: [Microbiology] shaking incubator Message-ID: Dear members: Has anyone used the following shaking incubator for E. coli culture? How do= you like it? Dose it work to your satisfaction? I am looking for informati= on on this shaking incubator. Any comments would be greatly appreciated. Th= anks=2C Sissi Lab Companion=AE Digital Incubating/Refrigerating Shakers=2C 83L BENCHTOP H= EATED SHAKING INCUBATOR - 120VAC / 60Hz _________________________________________________________________ Windows Live=99: Life without walls. http://windowslive.com/explore?ocid=3DTXT_TAGLM_WL_allup_1a_explore_032009= From simin.xu from gmail.com Wed Mar 4 03:02:01 2009 From: simin.xu from gmail.com (simin.xu@gmail.com) Date: Wed Mar 4 12:04:02 2009 Subject: [Microbiology] Why the pH value decreased seriously in my algal culture? Message-ID: <3f1ac7cc-e050-4c14-8279-7e3b4cbfe457@e36g2000prg.googlegroups.com> Hi Is there anyone who would be so kind as to give me some idea to explain this phenomenon? I cultured several flasks of one green microalgae species in TAP medium under irradiance of 90 umol.m-2.s-1, I added 18g/L glucose in the medium, and after 9days of cutlure, I found the aglal culture in bad growth condition though the biomass accumulated was much higher than the control culture without glucose, the color of the algae showed a tendency of turning white!! I collected the cells and tested the pH value of the culture medium, and it was below pH4.5!! I think most of the algal cells must have died! The pH value in the control culture without glucose was 8.0. I checked the culture under microscope and no bacteria was found. I think the whole thing is very confusing :cry: The nitrogen source in TAP medium is NH4Cl, which should bring the pH down upon algal growth. So this could be a possible reason for the pH decrease in the above culture. But in another culture which also contained 18g/L glucose and under a much stronger irradiance of 800 umol.m-2.s-1. , the pH was 7.0 and with even more biomass accumulated!!! If NH4Cl is the criminal, then why the culture under stronger irradiance which should have taken in much more NH4Cl to produce biomass did not give a even lower pH?? Is it possible that the CO2 produced by respiration can cause a pH as acid as below 4.5? The following is TAP recipe: Tris - Acetate - Phosphate (TAP) Medium (modified from Durnford Lab) For One Liter of Medium: 2X Filner=92s Beijernicks Solution 25ml 1M Potassium Phosphate 1ml Trace mineral solution or 5ml P IV solution 2X (see SVM) 3ml Tris-Base 2.42g Glacial Acetic Acid (17.4 mM acetate) 1ml (pH should be 7.2) Stock solutions: 2X Filner=92s Beijernicks Solution (500 ml) NH4Cl 8g CaCl2 * 2H2O 1g MgSO4 *7H2O 2g Trace Mineral Solution (500 ml) 5 g disodium EDTA =96 dissolve in 400 ml water by heating and stirring Neutralize to pH 6.5 with 5N NaoH Add each of the following in order. Allow each to dissolve completely before adding the next. 0.5 g FeSO4*7H2O 2.2 g ZnSO4*7H2O 1.14 g H3BO3 0.51 g MnCl2*4H2O 0.016 g CuSO4*5H2O 0.073 g Na2MoO4*2H2O 0.016 g CoCl2*6H2O 1M Potassium Phosphate Stock (50 ml) add: 20 ml 1M stock KH2PO4 (1M stock: 6.8g/50ml) 30 ml 1M stock K2HPO4 (1M stock: 8.7g/50ml) pH 7.2 at RT From AMY.SALKINDER from uct.ac.za Wed Mar 4 05:44:03 2009 From: AMY.SALKINDER from uct.ac.za (Amy SALKINDER) Date: Wed Mar 4 12:04:26 2009 Subject: [Microbiology] Bacterial peptides Message-ID: <49AE779302000050000BF6AC@gwiasmtp.uct.ac.za> To whom it may concern, I am looking for the following commercially available peptides, do you perhaps know where i can get them from? -Chlamydia -Candida albicans -Staph. aureus -Tetanus toxoid -Mycoplasma -Mycobacterium geru -Gardnerella vaginosis -Trichomonas vaginalis Your help will be greatly appreciated! Many thanks, Amy ______________________________________________________________________________________________ UNIVERSITY OF CAPE TOWN This e-mail is subject to the UCT ICT policies and e-mail disclaimer published on our website at http://www.uct.ac.za/about/policies/emaildisclaimer/ or obtainable from +27 21 650 4500. This e-mail is intended only for the person(s) to whom it is addressed. If the e-mail has reached you in error, please notify the author. If you are not the intended recipient of the e-mail you may not use, disclose, copy, redirect or print the content. If this e-mail is not related to the business of UCT it is sent by the sender in the sender's individual capacity. _____________________________________________________________________________________________________ From farrlarr from isu.edu Wed Mar 4 13:08:19 2009 From: farrlarr from isu.edu (Larry Farrell) Date: Wed Mar 4 13:48:02 2009 Subject: [Microbiology] Re: Bacterial peptides In-Reply-To: References: Message-ID: Amy SALKINDER wrote: > To whom it may concern, > > I am looking for the following commercially available peptides, do you perhaps know where i can get them from? > > -Chlamydia > -Candida albicans > -Staph. aureus > -Tetanus toxoid > -Mycoplasma > -Mycobacterium geru > -Gardnerella vaginosis > -Trichomonas vaginalis > > Your help will be greatly appreciated! > Many thanks, > Amy > > Since the only peptide you list is the toxoid, it is a bit difficult to even suggest a source. The organisms that comprise the rest of the list make *lots* of peptides! -- Larry D. Farrell, Ph.D. Professor Emeritus of Microbiology Idaho State University From a_bernardo from hotmail.com Sun Mar 8 13:10:42 2009 From: a_bernardo from hotmail.com (=?iso-8859-1?Q?M=AA_=C1ngela_Bernardo_=C1lvarez?=) Date: Sun Mar 8 13:32:17 2009 Subject: [Microbiology] (no subject) Message-ID: Hi, I?m working in a project for my degree about enzymatic purification. We must choose one enzyme, analyze four protocols of purification and then write the "ideal purification protocol". I chose polyphosphate kinase, but I have found three protocols: from Neisseria meningitidis, Escherichia coli, Acinetobacter sp. Do someone know if there are more purification protocols of this enzyme? Thanks. Best regards, Angela _________________________________________________________________ Ll?vate Messenger en el m?vil a todas partes ?Con?ctate! http://www.microsoft.com/spain/windowsmobile/messenger/default.mspx From limbic_lesion from hotmail.com Sun Mar 8 20:25:12 2009 From: limbic_lesion from hotmail.com (N10) Date: Sun Mar 8 23:22:23 2009 Subject: [Microbiology] Re: E.coli MC4100 thi- genotype References: Message-ID: "Julian Spagnuolo" wrote in message news:mailman.310.1235494899.13724.microbio@net.bio.net... Hello fellow slaves of science. I'm trying to create a pspA reporter plasmid by linking the psp promoter using the thi- genotype of E.coli MC4100 as an auxotrophic marker, however I'm having 'a little' trouble finding out which gene has actually been deleted or mutated so that I can incorporate it into my plasmid. Does anyone out there know what gene the thi- in E.coli MC4100 actually is? Thanks, Julian HI Does this help http://books.google.co.uk/books?id=26hYh4sE3hEC&pg=PA280&lpg=PA280&dq=ecoli+thi+gene&source=bl&ots=JpvwCKh6ce&sig=WiNNumwyZnaaXhJK7ljyFO903YQ&hl=en&ei=mm-0SdWiB56Dtwfpx-3DBw&sa=X&oi=book_result&resnum=1&ct=result Best N10 _________________________________________________________________ Got a 2008 financial hangover? Find a cure at MSN NZ Money http://money.msn.co.nz= From tk from shaggy.csail.mit.edu Mon Mar 9 15:49:41 2009 From: tk from shaggy.csail.mit.edu (Tom Knight) Date: Mon Mar 9 19:19:00 2009 Subject: [Microbiology] Re: E.coli MC4100 thi- genotype References: Message-ID: > "Julian Spagnuolo" wrote in message > I'm trying to create a pspA reporter plasmid by linking the psp > promoter using the thi- genotype of E.coli MC4100 as an auxotrophic > marker, however I'm having 'a little' trouble finding out which gene > has actually been deleted or mutated so that I can incorporate it into > my plasmid. > Does anyone out there know what gene the thi- in E.coli MC4100 actually is? You might check the E. coli genetic stock center listings: http://cgsc.biology.yale.edu/Strain.php?ID=9973 They don't list this strain as thi-, but it could be part of the three deletion regions. From medanrc from yahoo.com Wed Mar 11 22:16:03 2009 From: medanrc from yahoo.com (mohamed eda) Date: Thu Mar 12 11:46:07 2009 Subject: [Microbiology] inquiry about the Azurine cross-linked (AZCL) substrates Message-ID: <193142.16461.qm@web65512.mail.ac4.yahoo.com> Dear all I hep you are fine and doing well I want to measure the enzyme activity (cellulose and himicellulose degrading enzyme)? for fungi , I found one paper (Screening for cellulose and hemicellulose degrading enzymes from the fungal genus Ulocladium) but it is not clear in the methodology how to prepare the the Azurine cross-linked (AZCL) substrates e.g(amylose, arabinan, arabinoxylan, b-glucan, casein, cellulose, collagen, curdlan, dextran, galactan, galactomannan, pullulan, xylan and xyloglucan) so, I need help in the preparation of these substrates. thank in advance Mohamed Mohamed Eida Agricultural Microbiology Dept. National Research Center, Egypt Hiroshima University Graduate School of Biosphere Science Assessment of Environmental Dynamics Dept. Plant Environmental Science Lab. phone No. 090-6405-4222 (SoftBank) From cookd from mccc.edu Mon Mar 16 12:13:58 2009 From: cookd from mccc.edu (Dawn Cook) Date: Mon Mar 16 16:15:41 2009 Subject: [Microbiology] crystal violet Message-ID: Hello, I like your CV recipe, but I have a question. Lots of crystals turn up in the gram stain. Students think they are beautiful bacteria! What do I need to filter to rid the CV of crystals, the end product or one of the ingredients. Do you filter? If I went the easiest route and let it drip through filter paper, what porosity would you suggest? Hoping you can help, Dawn From jmglezh from ull.es Mon Mar 16 17:00:19 2009 From: jmglezh from ull.es (Jose M. Gonzalez) Date: Mon Mar 16 22:56:04 2009 Subject: [Microbiology] Aerobic Pseudomonas Message-ID: <20090316220019.sz0xphtym88c8wc4@correoweb.ccti.ull.es> Why do we teach the students that Pseudomonas is an aerobic organism when we know that it can grow in anerobic conditions with nitrate as electron acceptor? Where does this idea come from? Thanks, Jose -- Jose M. Gonzalez Departamento de Microbiologia y Biologia Celular Facultad de Farmacia. Universidad de La Laguna ES-38206 La Laguna - Tenerife Spain Phone 34 922 318515 Fax 34 922 318477 Email: jmglezh@ull.es http://webpages.ull.es/users/jmglezh From limbic_lesion from hotmail.com Tue Mar 17 19:49:25 2009 From: limbic_lesion from hotmail.com (N10) Date: Wed Mar 18 09:55:56 2009 Subject: [Microbiology] Re: Aerobic Pseudomonas References: Message-ID: <3dWdnXye7vOF2F3UnZ2dnUVZ8gmWnZ2d@bt.com> "Jose M. Gonzalez" wrote in message news:mailman.539.1237262163.13724.microbio@net.bio.net... > Why do we teach the students that Pseudomonas is an aerobic organism when > we know that it can grow in anerobic conditions with nitrate as electron > acceptor? Where does this idea come from? > Thanks, > Jose > > -- > Jose M. Gonzalez > Departamento de Microbiologia y Biologia Celular > Facultad de Farmacia. Universidad de La Laguna > ES-38206 La Laguna - Tenerife > Spain > Phone 34 922 318515 > Fax 34 922 318477 > Email: jmglezh@ull.es > http://webpages.ull.es/users/jmglezh > Isnt it just the K 172 strain of P.aeruginosa which compies with your model ? Best N10 From DSpencer from Dal.CA.BLOCK Wed Mar 25 14:53:59 2009 From: DSpencer from Dal.CA.BLOCK (David F. Spencer) Date: Wed Mar 25 15:58:22 2009 Subject: [Microbiology] Re: E.coli MC4100 thi- genotype References: Message-ID: Julian Spagnuolo wrote: > > Hello fellow slaves of science. > I'm trying to create a pspA reporter plasmid by linking the psp > promoter using the thi- genotype of E.coli MC4100 as an auxotrophic > marker, however I'm having 'a little' trouble finding out which gene > has actually been deleted or mutated so that I can incorporate it into > my plasmid. > Does anyone out there know what gene the thi- in E.coli MC4100 actually is? > Thanks, > Julian I don't mean to appear unkind but I assume you have a reason to believe this strain really is a thiamine requirer? (It is true that many K-12 strains are). I have done some searching to trace the pedigree of MC4100 but I can find no reference to its being thi- (nor in fact for any of its ancestors). MC4100 is a derivative of MG1655 which is in turn a fairly recent derivative of W1485, a strain very close to the original K-12. It is through the W1485 derivative W2637 that W3110 was produced (W3110 being a fairly well-known K-12). Some of this is detailed in Barbara Bachmann's classic 1972 Bacteriological Reviews paper 'Pedigrees of Some Mutant Strains of Escherichia coli K-12'. I have never seen a genotype for MC4100 that mentions 'thi', and none of the ancestors of MC4100 are acknowledged to have a mutation in any thiamine synthesis or related gene(s).