Great. And I had the same problem some minutes ago.

Microorganisms you will find in 221B

Aspergillus fumigatus
Babesia (a dangerous blood parasite)
Clostridium botulinum (for scientific research only!)
Dobrava-Belgrade virus (commonly found in mice.)
E.Coli (everyone's favorite coli)
Fusarium domesticum (a fungus found in cheese)
Gulbenkiania mobilis (isolated from treated municipal wastewater)
Hydrogenophaga palleroni (a new genus of hydrogen-oxidising bacteria)
Idiomarina loihiensis (survives in extreme environment, e.g. the deep sea - perfect for 221B as well)
Japanese encephalitis virus (can be found in birds and pigs; transmission to humans through mosquitos in Asia)
Kurthia zopfii (can be found in meat and meat products, air, soil, animal dung, water, and milk)
Lactobacillus acidophilus (a good sign the household is still intact)
Micrococcus luteus (is found in soil, dust, water and air)
Natronomonas pharaonis ( a survivor)
O'nyong'nyong virus (Ugandan virus, weakens the joints)
Prolixibacter bellariivorans (Holmes et al. 2007)
Q fever causing Coxiella burnetii and Quadrisphaera granulorum from a laboratory-scale sequencing Batch Reactor.
Reichenbachiella (!)  faecimaris (I never want to hear again that bacteria are boring)
Sacbrood virus (feared by Sherlock) and Streptococcus pyogenes (Strep throat, scarlet fever, rheumatic fever, ‘flesh eating’ bacterium - sounds interesting)
Turneriella parva (strains have been isolated from e.g. tap water and from the uterus of a - harpooned?  - sow -)
Una virus (apologies to Mrs Stubbs)
Virus. In general.
Watson virus (Ok, not really a microorganism - it's a computer virus. "The Dr. Watson virus installs itself as a memory-resident program. It does not try to actively conceal itself. It infects files in a manner that makes disinfection impossible.") and  the funny named  Wigglesworthia glossinidia which lives in the gut of the tsetse fly
Xylella fastidiosa, is an important plant pathogen that causes phoney peach disease (specialist in faking, that is!)

Yersinia pestis (I've been waiting for this, it's so creepy) (notorious serial killer)

Ok - I'll do it. Though my Z doesn't fit that properly...

Microorganisms you will find in 221B

Aspergillus fumigatus
Babesia (a dangerous blood parasite)
Clostridium botulinum (for scientific research only!)
Dobrava-Belgrade virus (commonly found in mice.)
E.Coli (everyone's favorite coli)
Fusarium domesticum (a fungus found in cheese)
Gulbenkiania mobilis (isolated from treated municipal wastewater)
Hydrogenophaga palleroni (a new genus of hydrogen-oxidising bacteria)
Idiomarina loihiensis (survives in extreme environment, e.g. the deep sea - perfect for 221B as well)
Japanese encephalitis virus (can be found in birds and pigs; transmission to humans through mosquitos in Asia)
Kurthia zopfii (can be found in meat and meat products, air, soil, animal dung, water, and milk)
Lactobacillus acidophilus (a good sign the household is still intact)
Micrococcus luteus (is found in soil, dust, water and air)
Natronomonas pharaonis ( a survivor)
O'nyong'nyong virus (Ugandan virus, weakens the joints)
Prolixibacter bellariivorans (Holmes et al. 2007)
Q fever causing Coxiella burnetii and Quadrisphaera granulorum from a laboratory-scale sequencing Batch Reactor.
Reichenbachiella (!)  faecimaris (I never want to hear again that bacteria are boring)
Sacbrood virus (feared by Sherlock) and Streptococcus pyogenes (Strep throat, scarlet fever, rheumatic fever, ‘flesh eating’ bacterium - sounds interesting)
Turneriella parva (strains have been isolated from e.g. tap water and from the uterus of a - harpooned?  - sow -)
Una virus (apologies to Mrs Stubbs)
Virus. In general.
Watson virus (Ok, not really a microorganism - it's a computer virus. "The Dr. Watson virus installs itself as a memory-resident program. It does not try to actively conceal itself. It infects files in a manner that makes disinfection impossible.") and  the funny named  Wigglesworthia glossinidia which lives in the gut of the tsetse fly
Xylella fastidiosa, is an important plant pathogen that causes phoney peach disease (specialist in faking, that is!)
Yersinia pestis (I've been waiting for this, it's so creepy) (notorious serial killer)
Zavarzinella formosa (an aerobic, pink-pigmented, budding and rosette-forming bacterium found in a peat bog)

I think a pink Z is Sherlock-worthy, as well as a salt-tolerable Z-germ in the kitchen...
Baskerville is nothing against this mix 

Tobe, would you like to introduce our new project?

Sleep well and bacteria-free. 

Oh, with two teenagers at home this should be a piece of cake.

"Symptoms for Sherlock stuck in puberty"

Acne scar (right middle cheek, might be from chickenpox, but let's go for this explanation)

"Symptoms for Sherlock stuck in puberty"

Acne scar (right middle cheek, might be from chickenpox, but let's go for this explanation)
Bored all the time, except for his fits
Contradicting everybody (including himself)

"Symptoms for Sherlock stuck in puberty"

Acne scar (right middle cheek, might be from chickenpox, but let's go for this explanation)
Bored all the time, except for his fits
Contradicting everybody (including himself)
Dumping his friend via mobile phone

Eating disorder

"Symptoms for Sherlock stuck in puberty"

Acne scar (right middle cheek, might be from chickenpox, but let's go for this explanation)
Bored all the time, except for his fits
Contradicting everybody (including himself)
Dumping his friend via mobile phone
Eating disorder
Fidgeting and Fatigue taking turns

Giggling while sitting nearly naked in a posh place

"Symptoms for Sherlock stuck in puberty"

Acne scar (right middle cheek, might be from chickenpox, but let's go for this explanation)
Bored all the time, except for his fits
Contradicting everybody (including himself)
Dumping his friend via mobile phone
Eating disorder
Fidgeting and Fatigue taking turns
Giggling while sitting nearly naked in a posh place

Hanging around with homeless people and criminal graffiti sprayers